2WD to 4WD Conversion

[muleskinner]

Hi all, its been a long time since I've posted.
I have a unmolested '67 C-10 Fleetside, meaning all wiring and parts are original never hacked into. So that's why I want to keep it. Just feel lucky to have one this old without someone hacking away at it.Just want to know what years and vehicles I can use as a donor. Such as C-20 or K-10, K-20. I can find 4x4 Blazers that are basically junk that I think will work but wanted to tap into your vast knowledge base.I've done some research on here and seen some disagreements on the need for leaf springs in the rear.Also, are there any parts and can use from the 2WD such as inner/outer tie rods. it would be a shame cause I have less than 50mi on a entire new front suspension including the springs.