One of the more hideous things about rust is that it is completely indiscriminate in what it attacks. Rarely will you find just one individual panel with a rust problem. Yes, there are certain body parts that tend to show their rust before the others but that doesn't mean there isn't damage that you just can't see yet.

While rocker panels certainly are not immune to rust, they are also not usually one of the first to show the damage. By the time the rockers are rust eaten, you will most likely already need quarter panels, doors, and the floor. Such is the case with this '71 'Cuda. It also needs frame rails, the torsion bar cross member, parts of the firewall, and the door jamb pillar as well as some of the other parts AMD makes for this car.

So why did Muscle Car Restorations choose to start the rebuilding process with the rocker panels? We all know that all of the parts in a unibody car all work together to provide the support structure for the whole. What might not be quite as obvious is that the rockers are essentially longitudinal frame rails that connect the front and back half of the car. They also support the front door post, the rear door jamb pillar, and the torsion bar crossmember.

They also provide the reference point that determines the placement of just about every other exterior panel on the car. If the rockers are not placed correctly, it will be very difficult if not impossible to get the rest of the panels to fit properly. It goes like this; the rocker panels provide the reference for the doors. The front of the doors locate the front fenders which then locate the hood, front valances, and the grill, etc. The rear edge of the doors determine the fit of the quarter panels which locates the deck lid, tail panel, valances, and etc.

Since errors in the beginning tend to be multiplied with each successive panel, it is critical that the starting point be as accurate as possible. That means that the car itself must be checked to be sure that it's not only square from one side to the other but that the entire framework of the car is within factory specs before work begins. That is accomplished at a competent frame shop that can not only measure the car, but pull it back into shape if necessary. Since this car was known to have been hit in the rear at some point and the resultant collision repair wasn't entirely accurate, it was critical that the frame rails be put back to factory specs so that they could be used as reference points for the rest of the car.

See all 18 photos No restoration project is going to come out right if the foundation is not square to begin with. Even though most of what you see here, including all of the frame rails, is going to be replaced with AMD parts, MCR sent the car to a frame specialist to check and put the major reference points back to their factory measurements.

See all 18 photos If you are going to be replacing the rockers, it's practically a given that you are going to have to replace the floor too. This is fortunate in a way because it's much easier to replace the rockers with the floor out of the way.

See all 18 photos There are a lot of spot welds that have to be cut to separate the rocker panel from the rest of the car. Be patient, go slow, and know that there are some hidden inside the rocker assembly itself.

See all 18 photos The torsion bar crossmember connects to the inner rocker just behind the front door jamb. Since it is also going to be replaced, MCR just cut it off near the inner rocker panel.

See all 18 photos

See all 18 photos Go ahead and just cut off as much of the old rocker as you can to gain access to the inner spot welds that hold the panel to the front door post and the rear door jamb pillar.

See all 18 photos This is what is left after the rear of the rocker is removed. Note the square tube braces that keep the rest of the car in place.

See all 18 photos On top of the rocker inside the quarter panel is a small plate with a pair of studs that support the quarter window mechanism. It will have to be removed and spot welded to the new AMD panel.

See all 18 photos The new AMD rocker has the properly placed holes for the rear window support plate. MCR cleaned the plate and coated it with Copperweld before spot welding it in place.

See all 18 photos Even though MCR thoroughly braces the entire car, they still take and record extensive measurements to verify that nothing has moved before the new rocker is fitted.

See all 18 photos Clearly there is more repair work to be done to the inner panels here, but this gives you a good idea of the proper placement of the outer portion of the rear of the rocker.

See all 18 photos From the front, this is the outer portion of the rocker clamped in place.

See all 18 photos The vertical placement of the outer rocker panel is established by simply clamping it to the door post and the door jamb pillar. Fore and aft alignment is achieved by bolting on the door and aligning the leading line of the rocker with the leading edge of the door.

See all 18 photos Door placement is referenced off of the leading edge of the top of the quarter and the original quarter door jamb. This measurement was noted earlier in the project. Door height is set off of this reference as well.

See all 18 photos If everything is in order, the lower door gap should be even and approximately 3/8 inch.

See all 18 photos The inner rocker is fairly easy once the outer is in place. Fore and aft placement is achieved by aligning it with the outer panel. Again, note the bracing that keeps the rest of the body parts from moving out of position during the repair.

See all 18 photos The critical adjustment for the inner panel is the height. It can only be set by referencing off of the torsion bar cross member. Replacing the cross member is the subject of a future article, but for this purpose, its position is determined by the front frame rail and the jig post under it that is welded to the frame rack. No welding will be done until the rest of the parts are in place and everything's fit is verified. Until then, self-tapping 1/8-inch screws take the place of spot welds.