[JM 35 Sedan]

IMHO, if you want to run '40-'48 wheels on the rear of your car, replace those '35 hub/drums with '40-'48 hub/drums instead of grinding those 5 nubs off the '35 drums. '35 rear drums were one year only, not reproduced to my knowledge, and getting difficult to find for those who own '35's and run with stock wires. If they measure less than 12.060" dia. at brake shoe contact surface you could probably sell those, buy good '40-'48 rear drums, and have money left over.
As others have already stated, your front drums look good to go with '40-'48 wheels, assuming they do not measure over 12.060" dia. in the brake shoe contact surface area.
Also, I picked up some 16", 5 on 5-1/2" bolt pattern '40-'48 pass. car style wheels, that measure 5" wide in the tire bead area. They were being used on a late '40's to early '50's pu truck that the owner was changing over to 15" wheels. I believe he said they were original factory wheels that came with his truck.