Saginaw Specifics
When looking at a Saginaw transmission, the front input shaft will likely have one or multiple grooves cut around its diameter. These grooves are there to indicate the ratios of the gears inside the transmission.
0 grooves: First 2.84, Second 2.01, Third 1.34, Fourth, 1.00
1 groove: First 2.54, Second 1.84, Third 1.44, Fourth, 1.00
1 groove: First 2.54, Second 1.84, Third 1.32, Fourth, 1.00
2 grooves: First 3.11, Second 2.20, Third 1.47, Fourth, 1.00
3 grooves: First 3.50, Second 2.46, Third 1.65, Fourth, 1.00 (I believe ours has three grooves so it's this one)