[SatanicMechanic]

Weigh the truck. If you have truck scales around, they will weigh the truck for free. Do this before the conversion, after you stripped out the pickup and after the conversion. This will tell you how much you have gained or lost. Also see about weight distribution of the S-10.
Before converting, measure the space between the bottom of the fender above the top of the tire to the top of the tire. Do this for all four tires. After the conversion, you will want to keep the same space within +/- 1 inch. If it goes beyond that, your weight distribution is off or you need beefier shocks or springs.
Don't worry about the S-10's computer and instrumentation. All you need is the speedometer. Most of the instrumentation on the dash is warning lights to sensors that you will rip out anyway.