Application Specific: Tap-Tite or Capscrews

[Citroënbender]

That rotten W126, but it’s a more general question about which approach is most likely to suit.

Exhibit A, the window motor and reduction gear assembly. Due to heavy loading of the system, I desire to open the housing and renew the old, dry/stiff greasing.

There’s four peened securing points holding the plate steel cover onto the cast alloy housing. To get it apart, I’ll need to counterbore them.

When re-fixing, with basic bench facilities including a Chinese drill press, is it going to be smarter (less risky) to drill for tap-tite style screws, or drill and tap? I think the thread would either be M3 or M4.

I have to process at least three motors, possibly all four; that’s 12-16 holes where failure isn’t an option.