Starter Solenoid Issue

Has anybody had an issue with their starter solenoid corroding or burning up? During my inspection I see streaks underneath the solenoid on the firewall and the top of it looks corroded or rusted. I got the one from Vans using it with a B & C starter. Using a toggle to turn on and off. Going to replace it but not sure to go with the one from Vans again or get a Lamar model from ACS.

Solenoid

Use the lamar, bought mine from amazon. Cheaper than acs

They are pretty robust and simple electro mechanical devices. My guess is the contact disk is sticking causing localized pitting and high heat. Overheating would explain the appearance of the top metal cap and the streaks.
You can do a post mortem inspection. Drill out the rivets and take it apart.