1972 C10 2WD to 4WD Conversion?

[coche1]

Hey all, new member here. Here's a bit of backstory for me: I have wanted a 67-72 C-10 for about 15 years or so - I fell in love with their style as a teenager. About 8 years ago I finally bought one off ebay with the intention of restoring. Long story short, I don't have a valid title for it (or any title for it for that matter) nor do I have the time to do a complete restoration with a toddler at home and hopefully a second little one on the way in the next year or so.

So, I've been keeping an eye on the classifieds and I've noticed that 4WDs are much less common than 2WDs in these old trucks at a reasonable price for a 'daily driver' condition. I happened to stumble across a 1972 long bed, 2WD C10 with a 400 small block and 250 turbo transmission. My truck is (I believe - again, long story) a 1970 with the original 292 straight 6 and manual transmission.

How difficult and expensive would it be to combine the 2 trucks and make 1 4WD with the 400 small block and auto transmission? Is there any kind of 'adapter' transfer case that you can bolt on to convert the 2WD to a 4WD, or would I basically need a whole new transmission? I'm not up for tearing into the innards of the tranny and swapping out parts.

The 400 small block/250 turbo trans is kind of my dream setup in one of these trucks with 4WD, but I can't see buying a 2nd truck, doing all the work to swap out the rears and drive shafts and everything from the one that I already have, and then having to replace the transmission on top of it when the truck I'm buying is already a daily driver and that's my ultimate goal... just with 2 more drive wheels...