some of my wiring is in pretty bad shape. the outer "wrap" has broken or worn away in a lot of places, but most of the actual wires' insulation is intact. my question is, is the oil pressure indicator sender SUPPOSED to be wired with bare cable or is the insulation just gone due to old age and oil leakage? i just changed the oil for the first time and shot sparks with the oil filter wrench when loosening the filter because it touched the bare wire (and possibly the starter terminals) and so i was wondering if thats supposed to be insulated or not and how i would insulate it if it needs to be. the indicator light flashes seemingly randomly as if there was a short. also, can i check the oil pressure with a compression gauge and a clever assembly of brass fittings? does it not work the same way? where can i get an in-dash oil pressure gauge?

a very greasy
handsome greg