I believe you will have to crank your torsions a little. You might be able to get away with some trimming and ziptieing. It all depends on how your stock settings were. Each truck is different and it depends on what rims/backspacing you are using.
Your amount of turns might depend a little bit on mileage and wear. But you are for sure going to have to touch them and trim the lower facia piece. If you don't want to raise the t bars then I would suggest going with a 265.