How to weather seal a photo print

There's a bloke in Missouri who had the clever idea of scanning the faded and rusty steel fascia in his old Ford tractor instrument cluster, photoshopping the scanned image to make it look like new, printing the image onto photo paper and adhering it to the fascia, thus visually restoring the instrument panel. I have an identical tractor and am in the midst of a restoration, this bloke is kindly sending me a photo print to do the same with my instrument panel. His has been in place for about 2 years and he reports a small area where condensation has formed and caused the colour to run.
SO my question for the brains trust is does anyone know of a way to apply a moisture-proof barrier to a photo print without damaging it? My daughter cleverly suggested laminating but unfortunately the edges are visible so that's not going to work. I'm thinking maybe some kind of spray lacquer but hoping there may be some established process.

Would a clear coat like what is used on vehicle exterior paint work? It could react though...

There is a spray on sealer for maps and charts.
Can’t remember the brand name.
Good outdoor stores used to stock it.
The other is painted on
Aquaseal Map Seal Waterproofing for Maps | | Campmor

There is apparently waterproof inkjet paper.
Waterproof Inkjet and Laser Printer Paper - YouTube

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