With my Rangemaster Treble-Booster pedal, all I did to finish the casing for the pedal was to first give it a wipe down with a piece of cloth soaked in Electrical Contact Cleaner to clean off any grease and marker pen ink, then I sprayed the outside surfaces with some grey etch-primer and left it to dry for a few hours, then I sprayed a few coats of acrylic Sky Blue spraypaint on the casing and left that to dry overnight, the next day I applied some letraset labeling to the case and then sprayed it with a few coats of clear acrylic, and then left it to dry completely before assembling the pedal, it seems to have held up pretty well, although the pedal has developed some "customized" relicing.