If its all torn down for sure go for the 335's if you have the cash.

im running 275 18's and i rub slightly on the inside and i used to on the outsides. i just took the chrome trim down a little and its fine now. 275's are the widest you can run without tubs

Man I hope you tub that thing or have deep pockets because you will be buying alot of rubber. Don't get impatient(sp) take your time better to do it right the first time then do it over. I have a 295 tire in the stock tub in back and it rubs on bad potholes and high speed corners. Just my .02