Here are pictures of two big trucks, both 46. The top one may be like yours in that there are two holes in the bracket which here are used with set screws. This is probably the way to go for you. The lower one is also factory looking but using no set screws. It is also very tight. Are you sure you have plenty of threads on your "pin bolts"? maybe your nut is tight before they close up on the door portion of the hinge..
If you tighten them up good with plenty of thread they should not move. Hope this helps.

http://www.redemerconcepts.com/truck/mirrorbrackets.jpg


When I yield to Him, it's amazing how peaceful and enjoyable life is meant to be.

1947 Chevy COE
In the Stovebolt Gallery
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