Different wheels across company lines isn't just an Imperial thing. Buick, Cadillac, Olds, all had there own designs too. All of that I learned from Steve's videos. Plus if it were easy, it wouldn't be as fun. Good luck
Imperial's had the own wheel size, bolt pattern, offset, the works. Steve Magnante on Youtube. He has lots of Junkyard Crawl episodes on Imperials. Check them out, he covers their specific wheels in nearly all of them.
Just a guess, I would think having them cranked up to clear your wheel\tire combo isn't good for the bar. My FSM says to measure 10 1/4 inches ( I think ) from the ground to the bottom control arm pivot at the frame. It seems to me if it's higher than that, you've got too much tension constantly...
Why not use a FI Tech FI system? Holley Sniper offers some options too. It would probably cost about the same only the reliability would be better. 2 BBL and 4 BBL styles are offered by each company. You've already got the return lines and presumably an in tank pump too. Just a thought.