I've never done the swap as far as a chassis swap goes, but I've been working on S 10s going on 20 years, plus have owned one for 15. As noted, the bolt pattern for the wheels is the same as 2wd (5 x 4.75), so one can simply use 2 wd S10 wheels, or GM RWD passenger car wheels. Those will get you the correct backspacing. IIRC, the 4x4 axle is about 4" wider overall than the 2wd.
