Modern Rodding Tech
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A-Pillar Splice typography
muscle car restorations technician prepping 1971 challenger pillar for replacement
1. Our project involves restoring the A-pillar on our 1971 Challenger convertible. The lower A-pillar on the driver side has already been replaced.
muscle car restorations technician prepping 1971 challenger pillar for replacement
1. Our project involves restoring the A-pillar on our 1971 Challenger convertible. The lower A-pillar on the driver side has already been replaced.
A-Pillar Splice typography
Bringing a 1971 Challenger Convertible A-Pillar Back to Life
By Mark Ehlen Photography Courtesy of THE MCR Staff
I

t’s no secret that few untouched E-bodies remain spared from nature’s wrath. Barn finds emerge now and then, but the vast majority of restorable ones are ready for a second go-around. This is beneficial in many ways, as it has prevented them from being parted out and scrapped. However, the downside of many of these cars is that their original restoration was often more akin to collision repair rather than an accurate restoration; the aim of the work was to make them look good but not necessarily correct. Often, correcting them would have required significantly more time, effort, and skill than was available for what might have been seen as minimal additional benefit.

Muscle Car Restorations (MCR) frequently encounters this situation in their restoration work. Previously repaired areas must now be redone to restore them to factory specifications. Naturally, the rest of the body hasn’t remained unchanged. Sections that may have been perfectly fine during the initial restoration may now require repair.

A good example of this is the 1971 Challenger convertible. The driver side lower A-pillar had been replaced; the lower corner was welded over part of the old one and then butt-welded to the top cowl to make it appear flush and part of the cowl, which it is not. The firewall and cowl are supposed to sit atop the A-pillar corner, with all three then spot-welded together. This repair served its purpose, was mostly hidden, and was likely undetectable to an untrained eye, but it is incorrect.

MCR is also helping in this case by replacing the firewall and cowl, which makes access to the A-pillar corner considerably easier. This repair could have been done without replacing those parts; it would have been slightly trickier. Perhaps that’s why the previous repair was executed as it was.

This project also highlights another common restoration issue: the difference between hardtop and convertible models. Some parts specific to convertibles are currently unavailable, so the same components of the hardtop versions are spliced onto the convertible section.

Since convertible A-pillars are unavailable and the top corner of this one (the part that differs from hardtops) is in good condition, MCR acquired a hardtop version from Auto Metal Direct and spliced in only the area that needed replacement.

This is a common practice with MCR: retaining as much of the original sheetmetal as-is reasonably possible. Only replacing the damaged portions of a panel can minimize the amount of the body shell that needs to be disturbed.

In this case, that’s truly the only feasible method for carrying out this repair.

interior view of stripped 1971 challenger showing rusted pillar and bare metal floor
2. At some point in the past, someone spliced the lower part of this A-pillar over the existing one and attempted to butt weld it to the cowl. This may have served its purpose then, but no reputable restoration shop would even consider leaving it this way.
freshly installed replacement pillar on 1971 challenger driver’s side
3. Here, you can see how the A-pillar is meant to fit under the firewall and cowl. Naturally, this is much easier when the firewall and cowl are removed.
technician drilling spot welds on 1971 challenger windshield post
4. The center of each factory spot weld is identified and gently marked with a 1/8-inch drill to create a locator for the pin in the Rotabroach Cutter.
screwgun used to fasten 1971 challenger A-pillar patch panel
5. Removing the old spot welds is most effectively accomplished with a 3/8-inch Rotabroach Cutter. Remember where the last A-pillar was cut and welded to the original part.
technician using cutoff wheel to remove damaged pillar section on 1971 challenger
6. While MCR usually prefers to save as much of the original sheetmetal as-is reasonable and often splices in only the damaged section of a part, in this case, the upper end of the A-pillar on convertibles differs from the hardtop version and is not currently being reproduced. Therefore, MCR can only use the lower section of a new AMD hardtop A-pillar for this repair. That’s all that’s needed.
detailed shot of plug welds along newly installed pillar seam
7. You can clearly see where the last splice was made; however, since there is no damage further up the pillar, MCR will splice in the new part high enough to replace that as well.
belt sander smoothing welds on driver side 1971 challenger A-pillar
8. A 60-grit 3M belt file can serve as an effective alternative for breaking spot welds.
hand filing transition area between patch and original structure on 1971 challenger
9. It would be nice if all the spot welds fully cooperated and could come loose freely, but often they need a little persuasion.
rusted A-pillar and firewall section exposed prior to restoration on 1971 challenger
10. With the old part removed, the next step is to clean the surfaces to prepare them for new welds.
Welded-in and epoxy-primed A-pillar section completes structural repair on 1971 Challenger body shell
11. After the surfaces are cleaned, a coat of Copperweld weld-through primer is applied to prevent rust from forming between the welded surfaces. Note that the inboard lip is folded inward, making spot-welding that edge impossible. MCR has found single-sided spot welds unreliable, so plug welds will be used instead.
Full reproduction windshield header and A-pillar assembly for 1971 Dodge Challenger restoration
12. Since a convertible-specific A-pillar is unavailable, MCR will use the lower portion from the hardtop version. If the top corner of the A-pillar is also rust-damaged, MCR will form the necessary part from scratch.
echnician grinding weld edges clean on a Challenger A-pillar using a rotary sanding disc
13. With the new AMD part cut to fit, the next step is to remove the e-coat that protects the part from rust in all the weld areas. E-coat interferes with the welding process, and while spot welding can be done through the e-coat, MCR prefers to remove it from all weld areas. A 3M green bristle brush works well for this.
Epoxy-coated inner reinforcement section ready for installation in the 1971 Challenger pillar
14. A good coat of Copperweld protects surfaces from rust without interfering with spot and plug welds.
Spot weld holes drilled on reinforcement channel for plug welding into Challenger A-pillar
15. The Rotabroach Cutter also creates holes of the correct size for performing plug welds.
New A-pillar clamped and test-fitted to 1971 Challenger for structural alignment and gap checking
16. Before starting any welding, ensure that the part is positioned correctly and securely clamped in place. It cannot move at all or significant problems may arise.
MIG welder applying plug welds to secure new A-pillar section on 1971 Dodge Challenger
17. MCR uses spot welds whenever possible, however, since there is no access to the weld area on the left, plug welds—a perfectly good alternative—will be necessary. Once ground down, they essentially disappear.
Replacement A-pillar installed and finished smooth on 1971 Challenger shell after plug welding
18. This is how the repair should have been completed last time. Now that it’s correct, the new firewall and cowl can be installed next.
SOURCES
Auto Metal Direct
(833) 404-4777
autometaldirect.com
Muscle Car Restorations
(715) 834-2223
musclecarrestorations.com
Modern Rodding
VOLUME 6 • ISSUE 59 • 2025
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