It seems like there would be way too much play between pto and impeller . I know if you pull the engine you have to use an alignment tool . So that tells me it travels very high rpm . It seems like it being shorter would cause more vibration .
They said it will be tomorrow before their R&D give me a call. My original shaft is 23 5/16 the revised shaft is 23 3/16, at first they said both work fine in their test. Is that really much of a distance to worry about?