Cause effect People that where buying the Penzoil tended to be cheap. Cheap people tend to push not changing oil.
Slugged up air cooled engines are a sign of neglect, abuse and heat.
We had the same with a Tracer my wife had back in the 90s hail damage Took the money paid it off free car is what she called it. next summer on about a 100 in the shade day parked it in the sun late afternoon most of the where gone used some ice blocks to shock a what was left and the last of...
For an " Elite " product with all the time in to the housing why would you not uses a break out OEM Connector Tap wires are for hacks will cause problems later for owners. Never cut a wiring harness.