There are some posts o nthis subject at RamchargerCentral.com and Pirate. The big pieces you'll need to get are the front axle (a Dana 60), transfercase was married to the transmission for your model (probably an NP241 or NP205 for the stick), engine cross member is different, trans crossmember is different, the rear is lifted with 4- or 6-inch blocks from the factory. Then there are potential differences between the cabs...some had removeable trans covers, others don't. Then the linkage, front driveshaft, steering change, front spring mounts, shackle mounts....it's a big task with many parts, much time and $$ for the conversion. It is possible.

Then there's the advice to look for a 4wd frame, ready to go, or another entire truck.

Four Wheeler ran some articles a few years back on the conversion of a 70/71 Chevy C20 to 4wd, all the same concerns, good documentation.

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