I have a 36 Master Town Sedan. It should have the same fuel pump as your 36. There were an assortment of fuel pumps available for that engine. The one that was on my engine when I got it was an after market one and the check valves in it leaked. That pump had press in checks and would have to be sent out for rebuilding. Not many shops have that type of checks for my pump any more. I found an original type replacement from Doyles Carburetor in Georgia but he has since passed away. You might check with Gary Wallace in Missouri. You can also post in the parts wanted section of the VCCA website. You do not have to be a member for that. There is also a section for Trucks on that site that may have more information for an early model such as yours. If you need some other leads for mechanical parts for that engine send me a pm.

Just so you know, 36 was a big transition year for Chevrolet. That is the last year of the 3 main bearing original stove bolt 6. It is also the first year of the full water jacketed engine. So in other words a one year item. It will serve your friend well for MANY years as long as he does not over rev it.