I imagine you are referring to your '65 GS?
If that is the case, a '65 has a 12 gauge purple wire and a 18 gauge yellow wire that go to the starter with the battery cable. For some reason, Buick switched the color at the connector you have pictured. The purple wire is purple in both male and female connectors. The 18 gauge wire is pink in the engine harness connector , then goes to yellow at the starter harness. Always thought that was weird for Buick to have done that.
The '66 harness is not identical to the '65. Just finished redoing a complete '66 harness set for gs spoken here. Found a few differences from the '65s.
Loren