Actually that’s a big help 🙂 All I know is that it came from a guy who collected a massive pile of stuff over the years from RAAF Laverton so it really comes down to what may have been scrapped there. If your engine theory is correct it would be great if it had come from something such as a Bulldog or Wapiti, but that’s just my pipe dream 😎 Will see if I can find a parts list for either engine you mentioned and see what turns up

Cheers

Ewan