Fronts? rears? which ones?
I recently tried some 15x8's (5.5" backspacing) on the rear and they would have required way too much caliper grinding, or the use of about a 3/8 spacer to get them to work. So I didn't use them (I started a thread about them here in this section several weeks ago, it has a pic, too).
For fronts, I have a pair of 15x3.5 skinny rims that I'm trying to sell now. They have 1.75" backspacing, and would require a spacer to use, as most skinnies do. And as a result, longer wheel studs, or one of those spacers with wheel studs in them. I've considered using one of those that is 1" thick with the studs in them, instead of using a separate spacer and installing separate longer wheel studs.
One thing for sure, those drag lites are nice and lightweight!