[jambo]

I don't have a wiring diagram anywhere handy, but I believe the oil light is a switched earth, that is that it should be a positive to the bulb, and the lead to the oil pressure switch is the earth, which is "made" if the pressure is below the operating pressure of the switch.

Have a look at the wiring diagram and see if that seems like it would hold true, I'm unsure if the same would go for neutral or not.

I seem to remember for the curvy that the fuel sensor was essentially a pair of thermistors or similar, so they didn't straight switch but varied resistance depending on if they were submerged in fuel. If that's the case then you'd need some kind of switch driven from those values. That is, however, a very vague memory of a conversation based around building a set of clocks for an earlier version of the bike.

Jambo