Hello. I can probably help you and will be happy to exchange messages in more detail on Monday. You mention the T9 gearbox was a conversion, so I make the assumption you have a 4/4 which originally had a 4 speed gearbox. I converted my 1971 4/4 to use a 5speed T9 box in the 1980s and wrote up the conversion details in Miscellany at the time. If that report is of help to you I can email a copy, if you are converting a T9 back to a 4 speed, I may also be able to help. Mike Pullen.
