The passenger side sideview mirror of my 1989 fc shakes when at speed. I looked at possible ways to fix this, but I cannot locate the screws that need to be tightened. It’s mostly loose in the top left corner. I see the two screws keep the housing on the mirror cap, but I can’t see any other screws to tighten. Any help is appreciated.

Google instructions:

Tightening Wobbly or Shaky Mirror Glass
If the main housing stays put but the glass itself wobbles or droops in the wind, tensioning the inner components is necessary.

1. Adjust the mirror: Manually pivot the mirror glass as far inward (toward the car) as possible.
2. Locate the screws: Look behind the glass for the adjustment mechanism, which features small screws or swedged tabs.
3. Tighten the screws: Use a stubby Phillips head screwdriver or the appropriate hex tool to carefully tighten the screws found inside. Be careful not to apply too much pressure directly against the glass.