[Synchro909]

Take it from me, Brooklands type windscreen are virtually useless - for show only. Even the slightest drizzle of rain feels like you are being shot with a barrage of needles and in decent weather, you will be wind burned to a crisp in a flash. Been there, done that.
I would go with a standard Model A windscreen from an open car chopped down to your liking that will give some degree of protection. Modify the stanchions so that it can be folded flat if you like.