I only had one memorable tank slapper in over 60,000 miles and I can't remember whether the fairing was fitted at that time or not.
I padded out the seat over the standard cover and topped the lot with a vinyl cover, fixed with stainless steel screws into the seat pan
When the extra cover was removed, the screws (not rivets) were replaced.
There is a Peter Furlong full chaincase fitted too, for those that like period extras.
Don't expect too much of the performance - but I am not disappointed. It always needed its neck wringing to make good progress.