Here's a factory solution
http://rides.webshots.com/photo/2098090740080251109GXrVzK
I know it's not your truck, but it is an original 37 GMC.
You could easily duplicate the idea to suit your truck, and even tell folks that's how GM did it....

Grigg


•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-