I have a 1940 Ford sedan, I am building the car in stages, I would like to put a leaf spring kit on the rear and run a 8'' rear end,Would like to know how to run a open drive shaft to connect to the stock 3 speed ,Looking for ideas or a method ,truck trans,kits,custom drive shaft,ect. (new to this site and just learning to navigate around) Chris in DENVER
Get an open drive 3 sp tail end and mounting casting and put it in your 40 box..........or get an open drive 3sp and swap the box out.
you need the output shaft and tailshaft/mount from a 39 to 50 ford half ton three speed truck trans to be compatible with your gears and box. i would pull yours a part and inspect all of the gears then take your first/reverse slider gear and output shaft and make sure it matches the truck trans output shaft (they changed the spiral cut on the output shaft in i belive 51.) you could also use an entire 1951 ford truck box column shifted, th box is stronger, diamond cut gears and needle bearings instead of caged needle bearings. just do your home work and check all parts for compatibility because ford made aton of three speed flathead boxes and gears that all look similiar but had subtle differences.
i used guts from a 47' ford truck with a 6 popper. Just the guts from the case, and they fit right in my 39 toploader case
Search (flathead open) on US ebay there are to sellers there regular. they sell the bits for the open tail shaft around $150 might be expencive for your taste, but at least you can eyeball the parts you need.