Hi Paul,...about sparkplug cleaning...i clean the plug with a small "acid" non-metallic semi-stiff brush using carb & fuel injector cleaner spray bath. Then after compressed air blow out, i use my small Benz-O-matic pencil flame torch to carefully burn off any left on carbon residue. Comes out lookin like 99 % new ! ...just amazing what a little flame will glow & harmlessly burn off !...tom.