Who has put a B-body 8.75 under their 70 dart?

Did you have to special order a specific back spacing? I looked on their website and everything looked like factory back spacing. I am debating whether to special order a set of steal rims and going with white lettered 15s with dog dish caps or going with the more modern look with the mustang Bullitt 17s.
What rim size and backspacing is working for you and what tire size?
5" BS on a 7" rim. 5 1/4" would have centered it perfectly. But this is in my case. Would need to carefully measure to see what you would need. Think a 8" with 5 3/4" BS would work well too. This is with a 65 B body rear.
Spent a little more for special order, turned out great.