fordsforme,I've done two t-5 conversions and I would purchase a t5 with mechanical speedometer.I believe 1988 went to electronic speedometer.The t5's were available into the 1990's s10 trucks.The 1352-145 1985-1986 t5 is the popular choice.Here is a link showing that a jeep t5 input shaft is 10 spline and will work with your original clutch with little modification.I will go this route next time.
t5 conversion the t5 page several t5 links for information Just give us a shout if you need some help!!
Tim