Great info... I had figured a 5.5" backspace based upon Nick's post in the link above. The 15x8's aren't recommended for the 295/50's but I do know folks still mount them without issue. The AR 200S wheels I need come in 15x8 or 15x10's only.

I specifically bought Firehawk Indy 500's tires because they do sell a 295/50/15 in that style...

Thanks for the post. Nice color/car... Looks similar to mine.