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1973
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Passenger-side Rocker Panel Replacement

Body Alignment

Before starting in on this project, I made sure that I had a stable and repeatable method of supporting the car. I did not want to distort the body while replacing the rockers. The rotisserie will not stop the body from twisting. So when the new rocker panels go on, the car is lowered down on to a home-built stand (in the rear) and a pair jack stands (up front). Then the distance from the car to the floor is carefully measured at all four corners, making adjustments as necessary until I am satisfied that body is straight.

I carried out this procedure in a part of the garage where the floor is nice and flat. I also put the doors back on so that if the body started to twist, it would be easy to see.

passenger rocker 01

The work is carried out where the floor is flat and free of cracks.

passenger rocker 01

I spent an hour or so building a stand so that the car would always be supported the same way whenever I worked on the rockers.

Rocker Panel Removal

I flipped a coin and began with the passenger side. When I bought this car, I naively believed that this rocker panel was solid. Wow, was I wrong... Just because you can't see the rust yet doesn't mean it's not there. After the car was stripped I could easily tell that there were problems here.

passenger rocker 03a

The first step was to remove a section of the quarter panel. I will eventually be replacing both quarter panels, but for now I'll leave most of this panel in place to help maintain structural integrity.

passenger rocker 03

See, it was in pretty bad shape even though it didn't look too bad from the outside. Most of the spot welds are pretty easy to find, but the ones at the bottom of the B-pillar were kinda tricky.

passenger rocker 04

The inside of the quarter panel. You can't really tell how bad the rust is until you get this section off.

passenger rocker 05

Many spot welds later, and some persuasion with a hammer and chissel, the rocker came off. What a mess!

Rust Repair

With the rocker panel out of the way, it was obvious that there were some rust problems in the lower parts of the wheel arch and inner-fender. I removed a section of the inner-fender and then removed a chunk of wheel arch. I had to clean things up and make some repairs at this point. This was the most time-consuming part of the rocker panel repair.

After carrying out the rust repairs, everything got a coat of POR-15 and weld-through primer before being welded back up.

passenger rocker 05aa

A seam weld inside the fender has to be cut to remove the the inner-fender section.

passenger rocker 05b

Wheel arch rust.

passenger rocker 05b

Repairs to the inner-fender took a while.

passenger rocker 05bb

Repairs to the lower wheel arch.

passenger rocker 05c

Things are starting to come back together.

Replacement

The rocker panels will be plug-welded into place. I drilled many 5/16-inch holes on a drill press, duplicating the locations of the original spot welds. I used 1/4-inch holes up front, where the rocker panel is joined to the front column support (lower A-pillar). I used 1/4-inch holes where the rocker panel is welded to the B-pillar.

When determining the location of the rocker panel, I paid close attention to front-to-rear alignment. I held the origninal section of the quarter panel in place several times to make sure that the rocker panel and quarter panel fit together just right. I spent a lot of time getting this right.

I left the factory e-coat primer on the this rocker. 3M Weld-through primer was used wherever bare metal was exposed.

passenger rocker 06

The new rocker panel was carefully aligned. I used the floor jack to firmly press the rocker panel against the lower B-pillar bracket.

passenger rocker 07

After the first round of welds, and the new rocker panel was securely in place, the car was lifted so I could more easily finish the welding. Note all of the bracing.

passenger rocker 08

Finished, side view.

passenger rocker 09

Finished, front view.

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