I've got a Factory Five car and am using North Race Cars (Richard Oben's) Team III wheels. They're 5-lug but he knows what fits. I'd recommend giving him a call.
As far as seats; I'm using these and I think they're great:
http://www.subesports.com/products/c...ra/prodID/1896
I had high-back seats; liked the comfort and support but didn't like the look. So I replaced them with the low-back Roadster SS seats that sit on these mounts:
http://www.breezeautomotive.com/deta...=250&cat_id=10
I ran a 3/4" square tube across the rear of the bracket to raise the rear of the low-back seats so that they didn't have as much rake.
Anyway, that's my setup as far as wheels and seats. I'm happy.