where have my nuts gone?

Was switching screens last night and one of the well nuts dropped back into the void behind, any idea what I have to pull off to find it?
Thanks

Into the head mask? It pivots forward easily after you remove the top bolts.

Welcome............so tempted with

You need to wait a bit and your nuts will drop by them seleves ......... .

dah dah dah dah dah ........dah DAH......