Don't know if this photo will work and I don't have a good picture as my other account is locked?
It's there to stop any dirt, oil and water getting onto the clutch so worth trying to find and fit one.
I've not screwed my main cap in very far as it's plastic and can be a right pain to unscrew if you want to do your timing with a timing gun.
Mk1 78 Scirocco GLS 1.6 FR, weekend toy.
Mk1 88 Golf GTi cabriolet 1.8 DX. Daily drive.
Membership No. 323