I have read that they
(aftermarket service people who still handle Micrologic) break the case with
injected air pressure and give you a new one when the set is in for repairs.
That sounds crazy, but is it true? Any help appreciated.

Yes that's the way it's done. I was on hand when they "blew" mine apart. It
sounds to me like whoever did your mod really didn't do it. I had my memory
battery replaced and the mod done years ago and was told it would last 10 years
or so. I've had no problems. Mine was done by an ex Micrologic warranty
service station.
S/V Express 30 "Ringmaster"
"No shirt, no skirt, full service"