I'm getting ready to mount a passenger side mirror and I believe I remember a thread indicating that there are nuts welded in place in the passenger-side door already and all that is needed is to remove the door panel, find the nuts, mark the center with an awl and drill the hole from the outside of the door panel.

Am I missing any steps, or any helpful hints?

You are correct.

Thanks Mark.

Put tape around where you are drilling to keep the paint from pulling up or splitting.

And the nuts are the in the same position on the door, left or right. So if you are brave, you can measure the drivers door and transfer the measurements to the passenger side without going inside the door.

Pull the card and drill a pilot up through the center of the nut.

Easy way if you have a lathe you can make a guide via a proper bolt. If you have a steady hand you can drill the pilot out the center of the nuts. Process is not hard, but it was nerve racking for me the first time I did it.

I would also heat the area slightly to help the paint recover. Heat lamp works well or this. Tape is a great idea also as previously stated.

Thanks for the tips fellas. Thankfully (not sure that is right word) my paint was way bad when I bought it, which is why I'm drilling the holes now before I get it re-sprayed.

I'm sure it'll be nerve-racking for me too... no lathe unfortunately, just me and Mr. DeWalt.
- Don

Here’s a post from 2016

Passenger side mirror location

Garland,
Your search skills are far superior to mine. Thanks for the thread!

-Don

removed errant post

I did mine in a similar manner. First I taped a decent area around the holes in case of slips with the drill. I started from inside the door with a small bit to avoid cutting the threads in the existing welded nuts. I then used increasing diameter bits and a tapered rotary file bit to open the holes from the outside, taking care not to damage the threads.

After the holes were complete and cleaned up, I gave them a coat of primer and then touch up paint.

Thanks for the help fellas. Passenger mirror install complete!

After opening up the door panel and seeing how much stuff was the in the way, I decided to have a go at it from the outside....
Measured a few distances using my caliper on the driver's side... measure again... then blind measure two more times and transferred measurements to the passenger door. The first hole was off center a little, but was able to correct it as I increased bit sized. For the second hole, just used the rubber gasket as a template and hit it spot on.

Then used a bit of automotive paint along the drill marks and mounted the mirror. Now time for a ride.