If you’re putting 75 seats in a 75 car then you should be good to go. Double check now to be sure though. It’s the inner track on the drivers side that changed to reflect the added hump in the floor for the cat.
I don't suppose you have any pictures? I've googled til my eyes hurt but all I see are 70-72 tracks, which look like the ones I have as far as I can tell.
Oh, and the ProCar tracks look nothing like mine.
Last thing: were the inner and outer tracks linked? Mine has a side with the lever and lock, the other is a dummy track.