Is it possible to run 17x8 w/ fenderwells

You have fenderwell headers?

I don't know much of anything about fenderwell headers, but based on what I know about fitting 17x8" rims in general I would say no. At the very least if they could be made to fit it would be with so little offset and such a narrow tire that you'd probably be better off running 7" wide rims. Really if you're going to run tires narrower than 245/45/17's you wouldn't need 8" wide rims, and I can almost guarantee you won't fit 245's up from with fenderwell exit headers.