I'm not sure I follow your description. A 1 1/2 ton probably would have not come with a 5 speed, but that doesn't mean that it wasn't retrofitted. The most common were as follows:
Clark | Clark OD | Spicer | Spicer OD | New Process
24R | 25R | R24 | R25 | 124R
351 | 341 | 135 | 134 | 35

The top gear being toward the dash and the bottom gear being toward the seat. Note that the OD transmissions have 5th gear toward the dash. Except for New Process. They used what we called an X cover and both had 5gear in the same place. New Process was awkward because 1st and 2nd were beside each other. Clark had Reverse above 1st which was good for rocking a vehicle when it was stuck.