New fridge interior walls

[Yellowjacket]

Have a large freezer (5 c.f) and fridge (10c.f.) with top access in a 30 year old but well-built boat. Took out the old eutectic plates to install new system after condenser failed. Freezer is stainless, with holes, burnt areas, and silicone applied from multiple past installs. Fridge is formed out of a white slick board that is easier to clean.

I have to isolate the two boxes (was modified spill-over. Going with two smaller compressors), and would like to line the freezer with something newer and cleaner while I’m at it.

I don’t want to rebuild the boxes. My first thought was to slather some contact cement on the stainless and some white poly board, wait till tacky and stick them together, but now wonder if the cement will stick to a board designed to be unsticktoable. I suppose I could screw the board to the stainless, but that seems like a continuation of past abuse, an invite to future problems...

Suggestions from the knowledgeable would be appreciated. Brands, types, place to purchase (Home Depot) in the U.S. Thank you.