Most all Saginaw & Muncie Trannies have lines on the input shaft. The number of lines tell you the gear rations. The chart's below give you the ration info for respective lines.
Saginaw 3 Speed
Lines1st2nd3rd
No 2.85 1.681.00
1 2.54 1.501.00
2 3.11 1.841.00
3 3.50 1.891.00
Saginaw 4 Speed
Lines1st2nd3rd4th
No 2.84 2.011.35 1.00
1 2.54 1.801.44 1.00
2 3.11 2.201.47 1.00
3 3.50 2.471.65 1.00
Muncie 4 Speed
Lines1st2nd3rd4th
No 2.56 1.911.48 1.00
1 2.20 1.841.28 1.00
2 2.52 1.881.46 1.00
Second Design T-10 (Super T-10)
Lines1st2nd3rd4th
2 2.43 1.611.23 1.00
3 2.64 1.751.33 1.00
5 3.42 2.281.46 1.00
6 2.88 1.911.33 1.00
Here is some useful information that is not always easy to find.