What are you running for pics on your old big bolts? My 48 has the single arm. I saw a youtube vid of a 39 I think that had arms from the top of the cab or door??? I kinda like the style, and I need to see around a full grain box.
The mirror mounts on a single, long arm (tube) with a bracket that bolts onto the body at or near the upright that runs just ahead of the door. "Hot-shots" used more substantial mirrors mounted on both sides that fastened to the top of the door and near the low part of the window. I think the single-armed one is "original". You can buy replacement mirrors at any auto store.
In fact, I have one from my '51 truck. I changed my bed to a narrow design and am using the short-arm mirrors used on pickups.
I'd be glad to send you mine if you want it. $10 should cover the shipping and some. Let me know.
When I bought my truck it was in poor running condition and had only a drivers side older west coast mirror. I would like to have the single arm original style but I didn't want a poor substitute. I found a set of stainless steel heated, lighted, west coast mirrors on Craigslist and was able to use the mounting brackets that were already on the doors and that was a real plus as I didn't have to drill any more holes. I have a 15 ft. cab high grain box on 160 wheelbase so I also was concerned about good rear vision, they work very well for the purpose, I also added a 6 inch round wide angle to each side clamping them to the west coast arms so I can see along the side below the door glass - these were blind spots on my Low Cab Forward. They look good on the truck and I can see everything I need to.
Last edited by 78buckshot; Thu Sep 17 2020 08:53 AM. Reason: wrong info
1957 Chevrolet 5700 LCF 283 SM420 single speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto
Attached is the link to my '50 Chevy COE in the Gallery. Not the best picture but the driver's side mirror is stock for the Advance Design big bolts. It is not adjustable in terms of the length of the arm. The passenger side, which you can see somewhat better uses the stock mount but the mirror arm length is adjustable. These mirrors came on the truck when I got it. I did replace the original round mirrors for the rectangular ones which I purchased from one of our regular vendors. These mirrors are adequate and allow me to see down the sides of the grain bed, which is 8 feet wide. This truck gets used, hauling firewood and also pine needles to the dump.