[37 Coupe]

If you do a search and mayby it is listed on Fordbarn vendors under John Connely or Columbia two speed .If you find his site for his rebuilding business in Temecula Ca. click on bulletproofing and it will show the band that is essentially the bulletproofing. I actually did my own machining and bulletproofing years ago with the guidance of another Columbia rebuilder Johnny Stooksberry I believe was his name. If you had a parts list or when you see John Connely's pictures you will see that part # A-24 the differential case was a poor design or poor machining.The four slots for the differential spider were machined with a straight cut instead of a perfect "U" shape and was inclined to crack in these four spots,think the case is cast iron if I remember,mine was cracked I do know this. The stainless or other type of steel band basically just reinforces this area. The guys who used Columbias to race with were the ones who had the most failures as I am sure the original designers did not count on drag racing abuse. Only people I ever heard knocking the Columbias reliability were old time drag racers and a guy I know in Canal Winchester Ohio that makes his own type of overdrive conversion.