There is now a kit, this is it.
http://www.thehollisterroadcompany.com/discbrakeconverion.html

There have been other discussions on the forum and projects in the works but nothing completed to buy or just bolt on like the kit above.

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
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"First, get a clear notion of what you desire to accomplish, and then in all probability you will succeed in doing it..." -Henry Maudslay-