Yes not a
problem.
The kit itself is basically a large thin metal washer and the black end cap which goes on the end of the gearbox. Costs about £11 from Seremotorsport on the forum so speak to Dave on here.
To change its easiest to take nearside wheel off and splash guard to get proper access. Using a large flat blades screwdriver prize the old cap off, doesn't matter about damaging it as your going to bin it. The spline you can see has back and forth play if you put your finger inside and grip it, will move in and out.... Over time causes whining under engine breaking etc.
All you need to do is un clip the large circlip that runs around the outer edge and take it out. Put in shim in its place and put circlip back in again. Pull the shaft out as far as it goes and the clip will pop back in, eliminating all play happy days.
Then tap new end cap back in. Job done.
I jacked my car up leaning to the offside slightly to prevent gearbox oil leaking out.
Mines a preventative measure as it is not whining or making horrible noises yet but so many people have used this kit to fix issues like this.
Hope that helps.
Stage 2 mk1 LCR 291bhp AmD tuned.