What are these wires

The second one is a grey wire and definitely the oil sender to gauge. Here's the somewhat common scenario.. When someone is jacking around with the distributor/timing, they knock that terminal off the sender. They don't notice the oil gauge inop or pegged to max right away. When that bare terminal shorts to ground it kills oil gauge the instrument voltage regulator and maybe screw up the fuel gauge in the process too if the tank is nearly filled.
Insulate/isolate that terminal !