On another forum, a member asked about 64.5 starter solenoids specifically for generator cars. He was unable to find anything out in the various catalogs. I relayed that there was some discussion about brown vs. other color starter solenoids, but that later solenoids should be compatible with the 64.5 generator. I can think of no reason why it shouldn't, as the charging system is distinct from the starting system. This was not for a concours-level car. However, he did raise an interesting question:
Is the 64.5 starter solenoid unique for its application in generators?