Thank you Elfen, this is very useful. Now that you mention it, I vaguely remember having used PC Exchange in the past. Since I have two complete sets of system floppies, there may be a copy of that application on one of them.

For the moment, my priority is to get the SE back to pristine, because I'm so attached to the machine. My brother jokingly observes that it has been with me longer than my wife, and that I have also fondled it far more often. Maybe that is an observation that we should not explore any further...

My feelings toward the 150 are a bit more ambivalent, since its first two hard drives died on me shortly after the purchase. They both got replaced under warranty, but in both instances the timing of their death could hardly have been worse.