I know the auto transmission bricks are somewhat sensitive but very sturdy if maintained and some say they are better for city driving... All my Volvos were standard shifters, Automatics are so much different to drive. I heard they hate to be revved in P or N, not to mention towing on rear wheels.
Sad story, I hope you and Dad can find a replacement soon, or as a `family-project`, convert to m46.
Pictures wanted!