I seem stuck at 6 minutes remaining - it’s been 6 minutes now for about 42 minutes.

I agree with the above comment. Also, it may help to know that the Monterey installation can take up to an hour do download, depending on network conditions, and another 45 minutes or so to install, with several automatic restarts. Go get a cup of coffee.

Nothing, in fact trying to rush an upgrade will do nothing but cause more pain and suffering.