d6b transmission

I have a new to me d6b 44a 11625. I'm trying to find out the transmission speeds, my parts book is for 44a6857-up but does not have the transmission listed that is in the tractor. Transmission # is 5m2961.
Is there a book for the higher serial # tractors?
Thanks for any help.
Farmhand

I have the later 44A6857 - 13071 (end production) parts book published 1973 but it does not show a 5M2961 transmission group either as standard or option.
Only other source I can think of to check would be the 561B pipelayer which I do not have a parts book for.

Edit: The transmission actually comes from an earlier 44A1-3874
First -2.0 mph
Second - 2.8
Third -3.3
Fourth -4.3
Fifth -6.0
Reverse
First -2.4
Second -3.4
Third -4.1
Fourth -5.2

Thank you OM for the information.
The trans serial number I listed is the plate on the back of the bevel gear case, guess someone actually changed the plate when they changed the trans.
Farmhand