Depends what you'll be wanting it to do. An S-10 is no more a truck than a Mustang II in my opinion, and if you ever want it to work as a truck, you would be well advised to freshen up the existing suspension and go with an unaltered drivetrain except for gear ratios. There are endless options you can explore, but the most tractable and versatile might be a rearend ratio change to, say, 3.55, and a transmission change to a T-5 from that S-10.
