Is it possible to fit a 9.5 inch wide rim on a KJ..
If so what offset would it need to be..
Running 18x8.5 with 245 tyres with no dramas..on King lows..

Personally I wouldn't recommend it as it's very close and too much stuffing around. In my opinion better to have wheels that will fit with optimum tyre fit and suspension setup. However, if you are that keen:

Haydensvrx ran that size, but he needed stretched tyres and suspension set up pretty specifically, also one of the vic guys, MGNTZE or someone?

This is from memory only... So best to check their ride threads.