Thanks for the follow-up on that.
Newsflash! After a major all-day episode taking apart half the MH (it seemed like), I got the S630 out and the Norcold 641.3R in, with the help of Number 1 son for the heavy lifting. MH door with its frame had to come out for one thing. :(
What a pleasure to have a modern fridge (from 2002 according to its certification) like we had in the 2003 5er. No more constant "issues" I hope . This 641 is running perfectly.
Thanks to you and the others who helped me keep the 1991 S630 going for the last two years--but enough is enough!