+1. I have the gearbox manual if you pm me your e mail.
But I had a problem with the dome that sits at the bottom of the gearlever this has a tang that engages to the extension holding the spring tight. The tang broke & it was a similar problem but with rattle from the gear lever.
Try first removing the grear knob & gaiter (the leather cover of the gearbox has to be removed) to see if the tang is broken. If not then it almost certainly is the bushes.
GoMog has lots on this
http://www.gomog.com/allmorgan/gearindex.htm
