Those wires are from memory
- Water temp sensor (basically a resistor to ground)
- Oil pressure sensor (also resistor to ground)
- Gearbox reverse light (two wire - shorts when in reverse)
- Starter motor trigger
So as Shinny said, just mess with them til they work. Turn ignition on then see which wires affect what on your dash then plug them up.
Hen
PS, from the colours in your pic I say the top two red/blue wires are reverse, the middle black wire is starter, and the two yellow wires are oil and water, unsure of which way round.