['ol Pinion head]

Burd, do you have any old listings of the test pipes???
Believe there are at leat 3 different test tubes for '75-80 Pontiac V8 equipped Birds.

My '80 SE's 301T had it's cat convertor shelved a week after delivery. There were no test pipes avail at the time from HO, Nunzi, or any local source, for that configuration of Cat. The 80 turbo cat has a ball joint on the front, & I believe, a slip joint on the rear. I went to our local late model yard & had the ball cut off a '79 useage cat. Then had the stainless ball welded on to a piece of exhaust tubing which was properly bent. Even though dissimilar metals, has held up since.