oil pressure switch wiring

hello everyone
just bought a mk1 cabriolet g reg kjet (finally in the club,bin along time)
got a bit of a problem though can anyone help
the top oil pressure switch wire/wires have rotted and i dont know which colour wire spades onto the switch, there are two cables near the switch when i connect one of them the oil light constantly flashes,when i connect the other nthing happens on the dash,if i join them the light flashes. i have run a test lamp from the positive on the battery to the switch and the switch is working
please help me  

blue/black wire is for o.3 bar cylinder head oil pressure switch

Yellow wire is for oil switch near oil filter head [1.8 bar ]     

Yellow / red wire should be for temp sender

Do not confuse these wires with the injection bits eg Thermo time switch [lilac/black wire] and oil temp sender [green/black wire].

Hope this helps ?

Cheers…………………..