Hi:
According to Mike Knell in his book "Chevrolet S10 Engine Conversion" the T5 Borg Warner was used behind the 4 cyl and 2.8 V6 until 1988.
A New Venture 5 speed was used in S10 trucks from 1989 until 1995. These newer trannys used an electronic speedometer and have the same torque rating as the full size trucks.
This book is a great source of info on GM engine conversions.
Ter