looked in the database and didn't see this combo for the rear......15X8 w/ 5'' BS. Will these fit 68-72? I am worried about it rubbing control arms. i do have aftermarket (Catapult) controls arms wich are thinner than the stock boxed (i think).

Well, it should fit - but it won't be centered in the wheel well. Really should have a 4.5" BS for an 8" wheel.

1/2" spacer maybe?

That could work, never used spacers before.