Memories of the F1 moving map display, though that had a lot of electronics in it instead of mechanical parts, though there was a heck of a lot of syncro systems in there to move the film in the carrier. We were using a whole pile of Mirage III autopilots that were scrapped as a source for the synchros, resolvers and gears as they used common parts for them. Those were all mechanical, a box you needed 2 people to carry ands 4 to put in the bay, all brass plates and gears, with thousands of ball races, generally at least 2 on each shaft, and hundreds of anti backlash gear trains.