Having checked the filler plug could actually be removed from the access hole I cut in the gearbox housing I made up this cover plate.
![[Linked Image]](https://i.imgur.com/tBcDXmT.jpg)
I lined the inside with a couple of strips of self amalgamating tape to provide a waterproof seal when tightened down.
Could be useful to a future owner if you wrote the purpose on the cover with felt tip pen?
Also, a note to others…be careful if you fold back the gearbox tunnel leather and insulation. If too tightly, the insulation can crease and may show up as a wrinkle when folded back into place.
