I could use some help figuring out which muncie I have. On the passenger side of the case running palleral with the tranny is 3925660 then below that is U.S. patent # 3088336 running vertical with the case there are two numbers the top one looks like P0Mo7A and below tha is (looks like) 1oK107366. On the side cover is the # 3884685. I can tell you that the imput shaft has ten splines and the output shaft has 27. I would like to know what year it is and is it a 20,21,22 thanks for any input.