Thanks everyone for your kind words. I tried to be faithful to the original while not disguising any newly made components. As some background, this piece came to me assembled in an old wooden building but with the correct proportions and all the tools and components assembled in their correct positions. As this building was made in the 1940s or even earlier, I concluded that the original tinplate building had probably been badly damaged and was discarded.
But I also concluded that it was used to reposition and reassemble everything in the new wooden building. I can imagine the original as a rusty hulk with broken glass, perhaps bent walls, flaking paint, etc. In those days people thought differently of old toys and the owner (probably the 2nd or 3rd owner by then) decided to make it look nice in a new building. He or she also added an old phonograph motor hidden in the roof to drive the tools although the original Marklin motor worked perfectly. Back then no one thought much about taking pains to preserve original parts and patina as we do now.
Scott and I were in almost daily contact regarding the progress of this project which he followed from the day I brought it home; he was often asking for updates which I was happy to provide. He was also an encouragement when things didn't go right which was fairly often. My biggest regret is that he did not live to see it finished.