Fit a new mainshaft bearing.

Fit first and second gear to the mainshaft, fit the mainshaft into the bearing and do up the the nut very tight.

Fit the clutch actuator locating pin (or screw).

Check the pivot pin through the clutch actuating lever is secure.

Fit the clutch actuator, aligning it with the locating pin in the housing and not forgetting the 3/8" ball underneath. Add a dab of grease to the ball, as the actuator sits above the gearbox oil level.

Do up the clutch actuator retaining ring. It is difficult to get it tight using a C-spanner.