I'm sorry to say I think step 5 is bad advice - after spending two days drilling out a stripped screw from the spare handles I bought, and after stripping the metal insert after two turns, and partially stripping the head on my passenger door handle (before giving up), I don't think those screws are designed to come out.
The Locktite is stronger than the glue holding the metal threaded insert into the plastic.
Unfortunately I fail at the better option of popping the button assembly out of the door with the door assembled, so I had to give up
I'll see if I can get the spares sanded and painted at a body shop, then have the dealer do the swap.