Go to the Tech Tips and look at the Transmission & Driveline section.

If you go with the S10, the first thing is to rebuild it and make adapters for it.
Then the downstream original drivetrain is usually removed to get rid of the torque tube and related parts.
You have to investigate and decide on what you want to replace it with. How good are you at fabrication?
If not so good, then I would look for a rod shop and pay them to do it for you.
If you end up with a 5 lug pattern rear axle then you have to deal with 6 lugs on the front axle or carry two spare tires.
If later you do an LS then the exhaust can interfere with the original steering box.
The steering box is usually replaced by something more modern.
While you are doing the steering box, people get rid of the straight axle for a MII suspension kit.
The kit requires someone with good welding experience.
The kit usually includes the 5 lug rotors.


If you really want to live on the "wild side" and save a wad of $$$, just install a 3.55 rear axle ring and pinion gears so you can at least get up to highway cruising speed.

"Adding CFM to a truck will only help at engine speeds you don't want to use."
"I found there was nothing to gain beyond 400 CFM."