I can't speak directly to your 53, but I can tell you that in 1983 I purchased an OEM visor for my Dad's 59 GMC and it was screwed onto the truck I took it off. It looked to me, when I took it off the donor truck, that it was factory installed. The visor was installed with screws on my Dad's truck and when he gave the truck to me in 2014 and we took it off as part of the restoration, it and the cab were in perfect condition and the holes made to install it were not rusted out or otherwise deteriorated. That truck drove gravel roads and winter roads all it's life too. When the truck was reassembled, the visor was screwed back on.
Hopefully this helps, but can't say I know much about the AD trucks and how the visors are installed.
