17 X 8.5 front 17 X 10.5 rear I have a 275 45 17 on the rear and have a good amount of room.. Where I live we have some great roads for driving on and did not want any thing to scrub.... Some set ups are way to close for anything I would run as hard turning would allow the tire to flex and hit the well.. I had Stockton build mine great rims poor customer service.. There is a old post on that but I waited a LONG time to get the wheels and then longer to get the correct rear wheels..
Opinions will vary greatly on this topic.. as I think bags are for grocerys...
but that is also why its so great to see all of the different approaches.. Its your truck build how you want it..