The holes for the ball are too large to redrill the new hole without welding up the old one,I think the difference is about a half inch. I forgot to mention the first time is to see if thats the problem is to take the inspection cover off and check where the fingers are on the throwout bearing. If you have the 37 bellhousing with the newer fork you will see the fingers are over the center to the pass side. Its not hard to change the bellhousing but you have to take alot apart and you have to remove the clutch and flywheel before you can get the bellhousing off. When you go to the junkyard bring a 9/16 swivel socket and extensions in case the motor is stuck. If you cant find any a local junkyard here has about five 41-6 trucks in it and if you get the bellhousing of a 41-6 dont forget to get the mount bolts too that year bell requires longer bolts

1937 Chevy 1/2-ton pickup