To be clear it's only because I had a fall and damaged the tappet cover and plastic that I pursued this idea.
I'd only have experimented if I had spare tappet covers to play with otherwise.
This is where I'm at
[You must be registered and logged in to see this image.]If the idea of a brass or stainless rub strip will work they could be bolted directly onto the tappet covers.
They should give protection without crash bars which Pete points out can damage the frame in a spill.
There's no way I'm interested in making these but if it was thought to be viable someone else may want to develop the idea.
I do intend to produce black fibreglass protectors for the tappet covers and bottom of the oil cooler shroud
because they will be easy and cheap for me to make but that's as far as I'll take it.