Throttle cable mod
An E-Fan conversion
Aerodynamic improvements (lower the truck, do some type of flat floor or an airdam/side skirt combo, you could experiment with a grill block too)
Appropriate tires rated for the intended speeds
Gear swaps
The Limas were used in circle track and drag racing classes for a long time. There are parts to get more power out of them, but they're getting less common all the time. Turbo stuff is probably cheaper and easier to find and make power with.
Here's an older thread on naturally aspirated 2.3 stuff:
As a former drag racer in a class where you had to use stock parts to make power (NMRA factory stock), I thought I would try my hand with the little 2.3L ranger motor for fun. My plans are to coax as much as I possibly can from my 97 2.3L motor using as much of the stock components as...
www.therangerstation.com