As far as the painted plate is concerned just make sure you polish or grind off the paint where the parts attach to it particularly the grounds and terminal strip mounts as the centre terminals are grounded to the chassis. If you have something like a Dremel tool the cleaning of these points is easy with a grinder or wire brush attachment. If you are concerned about numbering you can get a white or silver coloured pencil from an art supply store or a fine tipped paint pencil from a hobby shop. They work fine. Also you can get white grease pencils and just sharpen the point a bit.
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