Converted the rear drums to self adjusting with a ’63 self adjusting rebuild kit, Carlson and Rayestos are available and evidently cross to another year, which has all the parts to make the brakes self adjusting. Buy a 63 spring kit, file the head of the top spring “perch” pin a little to allow more room for the spring and the thicker self adjuster spring brkt. A 63 backing plate has the same size pin but the head that isn’t as thick, allowing for more “perch” room. Driver side backing plate needs a new slot cut in it back of center for access to the self adjuster sprocket and you have self adjusting brakes. Front self adjuster kit is not available as far as I found out but you may be able to use one for a car with same diameter drums. I put disc brakes on the front so didn’t need it. See pic for pass side rear with all installed.