37-40 brake drums & steering column tool

[wright-47]

Love the forums. I have been reading them for a couple of years and have got a lot of useful info from them. Would anyone have pictures or diagram with measurements of the 37-40 front brake drums. I am going to look at a set and want to know and see the difference from the 36s.
This is the tool I made to round out the steering column tube. Took out the dints and creases in about 10 minutes. Lathed to just fit the inside and pulled through with a slide hammer then dollied the tube with the flat part still inside