All of the posts I have found have been for the later style trucks, (late 40's to mid mid 60's) they have a lot more room in them as the 36 cab gets narrower from rear to front. Also not much room behind seat for a retractor. So thought maybe someone here on the site has installed them in this early style cab. But I will keep on searching, I'm sure I will find what I'm looking for.
As any of us who have worn a racing harness can tell you, a retractor isn't absolutely necessary. Just pick a suitable anchor point for the shoulder belt, and adjust it manually. You'll probably need to reinforce the area where the upper belt attaches to the cab. Summit or JEGS racing should be able to supply any kind of custom belt arrangement you decide to use. Simpson is one of the brands preferred by most round track or drag racers. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Here is how mine are mounted in a '37 Chevy cab. The upper mounts are heavy wall tubing cut to fit and welded to the cab frame and rear window frame. It was the best I could come up with, it would have to pull on the whole back of the cab before it will come loose. The lower outer mounts go through tubes that are welded to the seat riser and floor pan. The two center mounts are bolted to heavy wall tubing that is bolted to the floor pan with 4" washers and reinforcing plates on the under side. I used a standard 3-point belt with retractors from one of the suppliers who sell belts, nothing to fancy, just good solid USA made parts.