[02Lightning]

Check your turn signal/steering column harness. I had the exact same problem, but also had a broken turn signal cam. I replaced the turn signal switch/column harness and all is good. That however was on a Fairlane, but I think it's the same part & system.

Wiper motor, I don't know.

I had the same problem with my lights in my 69, replaced the signal cam and harness and all is good now.