Plenty of caliper clearance, probably about 3/8" before any contact. When I ordered I was asked about the clearance, the 17's and cast 18" have about 1.45" max clearance so those might not work but the custom 2 piece ones have 1.75" of clearance.
Fronts have a 6.25" backspace and the rears have a 5.25" backspace. Wish I would have gone with a little more space as the rears rub on the big bumps, but not much. Another 1/8" would be perfect.
Brakes are Dr Diff's Viper caliper setup with 13" rotors.
Sadly it is real. The muffler police were at the event with a decibel meter and told him he couldn't race because he was over the limit. So it was this or forfeit the entry fee.
Well that's a crappy response. Best method is to buy a cheap long reach funnel and cut the end off so it just fits over the hex of the bar. Then a little dish soap on the funnel and it'll slide right on. No need to heat it up.