How much of an undertaking would it be to add four-wheel drive to a two-wheel-drive square body. And how much will it cost?
The truck has a lot of sentimental value.
It would be an insane job you better off getting rid of that one and buying a four-wheel drive one
My thought is since the vehicle has a lot of sentimental value, why not just keep it as is and look for a 4x4 instead?
Don’t reinvent the wheel (no pun intended). Go to shows, inquire with 4-by clubs, and talk to people who have done it. Understand the process before you start buying parts.
BTW: this is a pretty good discussion if you want to start thinking about details:
https://4wheeldriveguide.com/can-you-convert-2wd-to-4wd-adding-4-wheel-drive-to-a-truck/
BTW: an easier alternative would be a “pre runner” style package: leave it 2-wheel but add a suspension lift, all terrain tires, locking rear diff, etc.
That's a massive undertaking, defintiely not a plug-and-play modification. The drivetrain in the front end requires a totally different crossmember compared to the one the 2×4 came with. You would need to pull that from a 4×4 and practically rebuild the front end from the ground up. You'd need to source the entire front drivetrain, a replacement tranny with a transfer case, cut a hole in your floor for the 4×4 selector, etc. Lots, lots more headache vs just buying a 4×4 model.
Find a donor 4x4, take the frame with drivetrain and plop the body of the 4x2 on the 4x4 frame.
You would need to find another similar year 4x4 Chevy pickup (K-series), lift it up, and transplant your body onto its chassis. I imagine there would be a fair bit of electrical work. You would have fab up a 4WD shifter mechanism. At that point ..... why not just keep the original 4x4 as is?
