Nice job Art.
I've seen registration stickers on aeroscreen equipped cars affixed to a plastic sticker holder used for trailers, and bolted to a rear over-rider. It was accepted by authorities as it was permanently attached, and used an approved holder, although for a trailer. They couldn't come up with a better idea, and so flagged it through.
It looks like you've kept the aeroscreen brackets very near to the dash capping, which should allow you to fit the windscreen and hood, should you want cover on wet days. At least that's the way it worked out on the last set I fitted to a friend's TR2.
Incidently, they supply self tapping screws to affix the brackets. I didn't trust them and used small CSK stainless bolts, washers and nuts. A smack on the head at speed with an aeroscreen isn't ideal.
Regards,
Viv.