18" wheels

Yeah, the "trick" is the Cobra wheels. Bullits need to be spaced back to ~5.6", the CobraR 5 spokes fit with the 5.72" backspace. The tie rod interference does depend on the specific design of the rim. I forgot about the Cobra R's being different.

Duster346 did run 17x9's later with the same Cobra R wheel, which have a 5.94" backspace. But when I asked him about it after the rally he said he was "on the tie rods and the fenders" with the 17x9's, 5.94" backspace and 275/40/17's.

Really it comes down to what size tire you want to run. If you don't mind running 255's then you can make a 17x9" rim work. But if you want to run 275's up front the backspace/offset window you have to work with is only about a 1/4", and it's from ~6" to ~6.2". And least without starting into significant fender mods. Tomswheels ran 285's on 18x10's on his Valiant, but he also pushed the fender out with a porta power. :D I know I could probably make 285's fit on my Duster if I rolled the fenders and pushed on the wheel opening a bit when I did, but with 16:1 manual steering I think I'm happy with my 275's.