[STREET BLAZIN]

Nooooooo, your doing it all wrong.....
It's harder to scrape the ground with a 4WD.
Gosh.
Well if that's what you need to do, then ok.
All of what crashz said sounds dead on.
The spring hangers are longer on the 4X, and everything should cary over to the new frame.
You may have to swap the floor pan to make room for the transfer case.
I know how easy these frames bend, when I stripped my blazer frame down, the frame rails just wobbled around like a noodle.
Make sure the frame brase in front of the engine and where the steer box mounts is good and rigid or it will walk all over the road.
Bigger tires will make it worse, I welded a strait frame brase in place of the old curved one.