Drain the tranny, pull the side cover off the transmission in question and look at the gears and 1, count the teeth, 2, check to see if they are at the front or rear of the opening, 3, check to see if they are spur or helical gears and idf so are they LH or RH helix. (look at your thumb) Then check the PTO your asking about and you will have your answer. If it won't fit you can use the information gathered to get a new PTO. Model information on a transmission that age will not be useful as the books/programs don't go back that far but a good PTO specialist can fill your order using the information I've shown you here.
The 39 has the torque tube drive shaft but doesnt seem as though that would be an issue. 