I would advise taking some time to get to know the vehicle before starting to build it up. Drive it around for awhile and then see what you NEED to get. If he plans on offroading a bit I would go for the 4x4 too.
:saw: :saw: and more :saw: and hell, maybe even some :welder: for good measure. If you want to make that fit. Can't you run 32's with trimming? I thought there was a post on here about that somewhere. If you want to run stock height though you should get 31's and you'll prob need to do some minor trimming.
I had 32x11.50's on my non-lifted 04 with 3.75 backspacing. it rubbed with the stock wheels and didn't with the aftermarket ones. I could see 33's fitting with a lift. It also depends if he is going in the mud or on rocks where flex is the key. It will probably rub, but it will be ok to drive with.
I would also say to go with a 4x4. If you dont, and go off-road, you will regret it