I just checked on it and it is an R10Q-1.
The truck is a 98% all original '72 C-10 with a 307 V-8 and a Saginaw 3-Speed on the Column. The engine has 167,000 Miles on it and still runs great.
There will be no problem finding out what the Rear has but, as I understand it, there is no way of telling what the 3-Speed Trans is without pulling it out. But I believe it almost has to be a 2.85 First Trans.
Thanks again, great pictures and info.
My next step will be checking the Rear Code.
