Disgusting, Rusted 1950s Rivarossi Locomotive - Will it Run?

Several months ago I was browsing eBay when I found an extremely rusty AHM RS3. I purchased the locomotive and ended up getting it running again however the seller also had a pair of Rivarossi 040 steam locomotives in similar condition, likely from the same flooded collection. After unboxing these locomotives it was clear the drive system was full of problems. Everything was seized and corroded and needed extensive cleaning before I could even disassemble each locomotive. Trying to get the motors to turn over was no small task since they needed to be taken completely apart without damaging anything. Surprisingly the windings on each motor turned out to be in working order. Fibreglass pencil (affiliate) https://amzn.to/49rvvKV