So I did pick up a set of the 1320 wheels brake conversion brackets. Then I searched long and hard for drilled/slotted or dimpled/slotted rotors for a early 90s K1500 reg cab light duty to run with those brackets (all people ever use are the stock smooth rotors but I wanted to match my fronts). After a few days I came across Brakeperformance.com. They have rotors in Stock and they machine and drill them in house and then ship them out, and you can get them in black zinc or silver zinc coated. The price was reasonable too at $170 for the set with ceramic pads. I bought acdelco calipers.
Also I'm not big on weight reduction and don't really do much of it, but I since the 1320 setup does not retain the parking brake (and nbs rear disc truck parking brakes never work anyway), I removed the brackets from the rear end, the shoes, the cable, cable brackets, parking brake pedal, release latch, etc. All of that combined and including the lighter rotors and caliper, the truck is about 100lbs lighter easily. The pedal assembly alone weighs about 20-25lbs and the cables another 20ish.
So now I can fit 15s, I'll be buying the same wheels I already have in 15s, but currently I'm waiting on someone to buy my wheels.
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