[5500 GMC]

I have a 1969 5500 GMC with a 351 V6 under a carpenter bus body
The transmission has a New Process logo with CS 5871 casted in the case, the service manual lists a 540GD or 540GL for the 5 speeds for this truck series
I have not been able to find any info on a CS5871 five speed by new process yet
the shift pattern on this transmission is low to the left and up, 2,3,4,and5 typical H pattern and reverse is to the right and up
from what I have read the 540 transmissions have reverse to the right and down
now for the rear end it is a hypoid, full floating axle with the numbers 3828111 ( the second number could be 3) and GM casted in the housing with what looks like D2 stamped below the casted numbers
any info would help