The Camper Saga. Opened a can of worms or mice..

Good job on the restoration.
Do not use the spray and foam, by itself, to fill the holes. Mice will still chew thru it. Go buy some "stainless steel" scouring pads and put them in the holes with the foam. The mice then can't chew thru. Mice and rats will chew thru PEX type piping, because they can actually smell the water thru the pipes. If you have any exposed PEX cover it up so they can't get to it. Also, PEX piping can't be exposed to any sunlight for more than 30 days.