That's a cool ad! Definitely looks like a GM product.
I decided to blow an evening digging through old GM parts books on gmpartswiki. This is partly because the rear shoes on my '57 appear original and are finally in need of replacement and I'm hoping I can scrounge up a forgotten set of shoes somewhere.
It looks like gm switched from 11 X 1-3/4 rear shoes to 11 X 2 rear shoes on trucks in '59.
Rear shoe part number 3695709 for '51-'56 changes to 3742645 also used for '57 models then to 3752313 then to 5470547.
Front shoe part number 3696177 '51-'56 changes to 3732507 also used for '57 models then to 3752312 same as F + R of '59 -'62 trucks.
GM says F + R drums are the same from '51 - '62 so maybe the larger shoes could be installed in the rear? I would guess the 59 + rear wheel cylinders would be machined to space the C/L of the cylinder 1/8 inch farther from the backing plate but that may not be the case. Maybe they use the same cylinders as the 55 - 57 front?
Checking through GM parts books it appears that 53-62 Corvette "Heavy duty" brake shoes also fit our trucks. Vette metallic shoes are part no 3794194 R and 3794191 F. Werner Corvette lists an OE set of F + R for $675.00. Still need the special heat treated return springs but it's just the thing for a guy looking to build a vintage hotrod truck with period correct parts.
