Patina get yourself a speedway motors catalog they will have everything you need including directions on how to measure for your spring.I have the same axle on my 37. ford used that style axle from I, believe, 35 through 48. Ford didnt use "juice" brakes until 1940. Mine was the original 37 with mechanical brakes.I pulled out my trusty Speedway catalog and bought the adapter kit for GM(Cadillac) disk brakes. In fact I used a 78 Cadillac as my donor vehicle. Mine has the Engine,trans,differential,& front calipers on it.Here`s a picture of how I "suicided" my front axle