http://uk.rs-online.com/web/p/protective-coatings/0714462/Where do you get conformal spray?
Hahaha cheers, think I'll let you try it first, your idea hahahttp://uk.rs-online.com/web/p/protective-coatings/0714462/
You probably want to get some PCB cleaner as well to prepare the board - RS sell that too.
Note: I've not tried/tested this yet, should work fine but if it fries your board, don't blame me!