Advice 2wd frame to 4wd frame
 

I currently own two 80's chevy trucks. One is a chevy c-10 that is very solid for its age. I also own a k-10. although the rear of the frame is completely rotted out and would cost too much to repair. i am wondering if i could make the 2wd frame a 4wd one. then i would swap the axles, engine and tranny etc from the k-10 onto the c-10. advice what to do? please need help with this one. my brother is a professional welder and could do it all at his shop. i just need to know what shackles are needed. i would replace the leaf springs and shocks with a lift kit.