For a 1941 passenger car all 4 drums are the same. They fit all cars with independent front suspension from 1936-1948 and all cars rear for that range. Also the rear brake drums for 1936-1954 trucks will fit your 1941.
Drums where cut before I got the car, I measured them and they are 11.380, This is way over spec,
I installed new wheel cylinders and brake shoes and i went to adjust the brakes and the adjusters are wound all the way out and i barely have drag.
One of the adjusters dropped the pin its so far over sized.
Thats why I need new drums.
As far as a cross refference book or compatable vehicals book, which ever you want to call it, it would be nice to have, I hace used these books in my other restoration projects but these where much later model cars (60's-70's era)
Also how do you get the VCCA member icon in your avitar, I'm a member and I asked to be added to the list so i can look at the member stuff. I did get a email saying they added me but I haven't seen the avitar show up yet.
Got my rear drums from "ROCKAUTO" for around $23.00 for a listed 1955 pickup. Had to inlarge the center hub hole a little so they would fit like they should.Been doing fine on my '47 stylemaster daily driver,for about a year now. I am happy davids(POPS)
PS Got most my brake parts from RA-quality parts & good price--jmo