what did this trans come out of?

i have a saginaw 3 speed that i got for free. it hase 3 splines on the input shaft. and the only number i can get off of it is on the side cover

3862846

its hard to read but i think i got it. any one know where i can fins this info. i have looked all over and cant match that number to anything

 

3 grooves means a 3.5 first gear and about a 1.9 second gear on that 3 speed .It would have been in a something like a G body Malibu with 2.70 something gears.

 

yeah i found the gear ratio im looking for more of the year it was built and what car it was in.