The dome shaped cup is part number UKC3159. Indelibly imprinted in my memory! I tried finding one for over 3 years! I found hens teeth and rocking horse poo easier to source! The tab that is used to bolt it to the selector case is the weak point. It is a known problem as gomog shows. A repair is possible by welding but add the extra tabs to stop it flexing and breaking again. I made a temporary tab to hold mine reasonably steady until I eventually found one by luck. New one had strengthening tabs. Also lubricate it to reduce friction against the lever ball underneath. Gear selection is better with a good fixed one.
Several owner clubs have similar issues for cars with the R380 box.
I kept the old cap in case needed in the future. It would need a new fixing tab and not yet done.
One other check is the bushes on the selector. Gomog gives details.
Also, how old is your clutch fluid? Basically brake fluid that needs changing as does brake fluid.
Clutch fluid is fine, it was changed along with the slave cylinder 3,000 miles ago.
The tab on the dome shaped cup is fine, there is a little movement if you try and move the remote housing so I’m hoping the bushes are the problem, I’ve ordered a set from Rimmer.
I’m concerned as there is almost no resistance to fore and aft movement of the gear lever, as well as being able to move it from side to side when it is in gear.
