Look at the casting numbers, serial number, Mac Van Pelts website will tell you. As far as the gears go I would say most later trannys take them, not sure about pre 36.
Look at the casting numbers, serial number, Mac Van Pelts website will tell you. As far as the gears go I would say most later trannys take them, not sure about pre 36.
Here is the location for VanPelts site: http://www.vanpeltsales.com/FH_web/flathead_home.htm
Most cases will have a serial number that can by dated using VanPelts site. Remember that the gears are what you are interested in and not the date of the case. If you are not racing the standard '39 and up gears will be fine and cheaper than the Zephyr gears.