Frame replacement for 72 Avanti

[Sal]

OK! I'm the guy with the car in the garage that I'm going to finish repairing some day. I've decided to either bind and gag my wife or have my eardrums pierced and get back to it. Some years ago an Avanti afficionado had written up a step-by-step 'how to' list to take the body off of the frame. Fortunately I remembered to print it out. Unfortunately, 7 years later I haven't the slightest idea where I put it. I have already bought a replacement frame that has been sitting in the yard, on the ground, patiently awaiting my return. Along with the instructions for lifting the body off without breaking it I have a couple of questions, not the least is; what is with the hog troughs? Are they really necessary? Wouldn't it be less expensive and a more permanent repair/replacement to weld a 3 piece ublar metal support from the frame to the rockers of each side? I envision doing this and placing urethane mounts between the added metal and the body as superior to the hog troughs.

Next: The wheels that came with the car are Mopar Wedge style. If these are Mopar wheels what are the hubs? Chevy or Mopar? I thought the trans was a 400 but was informed by the worlds foremost authority on everything that it is a 350, noting that turbo 400 is a truck transmission and wouldn't be on an automobile.

[Gunslinger]

The hog troughs are absolutely essential. They're integral to attaching the body to the frame, and it anchors the roll bar to the frame for torsional and lateral stiffness the fiberglass body can't provide. While the design was probably the least expensive method of doing so, it works. You could probably design some alternative method of doing the same thing, I can't see where it would be cost effective or do as good a job when you can buy new hog troughs ready to install and already engineered.

Your car, while it uses a Mopar/AMC/Ford bolt circle for wheels, it does not use those hubs. Your transmission may be either a TH400 or a 350...Avanti Motors used both depending on year and engine. The TH400 was not just a truck transmission...many GM cars used depending on engine, horsepower and torque ratings and car.

You should pick up a copy of the Avanti shop manual. It tells you the procedures for removing the body. The parts manual is a big help as well...lots of exploded diagrams which help make it easy to visualize what you have to do.