Yeah, the 2wd and 4x4 rear Wheel Mounting Surface (WMS) is different. I'm pretty sure that only applies to the 10 bolt (1500s,) however.
I believe the WMS for the 14 bolt is like 67.5", so assuming the '93 is thereabouts compared to the 2000, no problem. Swap it over. The 14 bolt 10.5" Full Float WMS are different for SRW, DRW, Cab & Chassis and Vans. There are no differences between 4x4 and 2wd, as far as I know. I believe the brakes are a bit better on the full float also, not sure on that.
Also good idea figure out ratios, just to make sure speedo is not off. On the 97-00 C/K3500 series, the 4.10s were standard, but earlier models went down to as low as 3.42s.
The 2wd trucks I've seen the front vs rear track width looks about the same, both wheels are kinda tucked in. But in the 4x4s the front is way popped out, but the rear looks about the same as the 2wd as
@454cid pointed out. Some guys hate this look. I had not really paid attention until a few days ago looking at my 4x4.