Ok, just for the record:
Printing the mouse.ps file on plain white paper doesn't work with any
type sun mouse
So I printed it on transparent paper, turned it over (so you don't
scrape off the print!) and put it on one of those dark shiny antistatic
bags , and on an aluminum foil: It works. But only with my type 4 mice.
RIP all you optical mice, and thanks for the suggestions.
Fred