need info on pre 40 trans.

[bsa48]

hello i need info about pre 40 transmission.. I believe it is a 38..... it is longer than a regular three speed one piece casting with a hump area at the rear and a control on left side... is this an over drive or an internal park brake..?

[RobertKB]

Pictures always help. 

[Semmerling]

On every case casting there is a number. If you can read the number, post it and there will be no mystery.