18x10 or 18x8.5?
#2
8.5's will be a lot easier to fit and you won't have to worry about anything. 10's are doable, but you'll have to run a pretty narrow tire (215/40R18 is what I would run) and have to roll and slightly pull the rear fenders. It also depends on what suspension you're running.
#5
Tens will look good, but is good fitment what you are going for? The 8.5s will look right, unless you space out the rears with pretty heavy camber. Also depends a lot on the offset. If the 10s have high offset (40+) and the 8.5s have low offset (15-) the 8.5s could end up being more of a problem. Idk xxr specs so...sorry. But looks like you are heading in he right direction.
#7
It's all up to you if you want to run an aggressive wheel setup or not.
The wheels you posted will fit, but you'll have to make them fit. They won't just bolt up with no worries. You'll have to roll the rears flat, plus a minor pull. May have to run equal camber front to rear.
#9
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