Brendendoucet

I have a 99 classic tahoe 4x4. It's been wrecked and every body shop I've talked to about fixed the bent frame is saying it can't be done I need to swap it. My question is can I swap my 99 frame for a 2000 yukon frame since that's the only one I've found? Or can I use a rwd frame and change everything over to it off my 4x4 to make it a 4x4 I'm not finding a clear answer on either one.