I'm not a fan of sticking anything to the top of the windscreen surround. Although it works, it has the disadvantage of looking unsightly when the hood isn't fitted - and this is 99% of the time. Dave's plan of gluing a strip of neoprene to the hood is much better, I think.
If one doesn't want to do this, or fork out for a better hood, the easiest way to deal with it is simply to recategorise the issue from being a "problem" to be an "endearing feature of driving a Morgan". It's only a few drips after all, easily dealt with by having a few microfibre towels handy in the cockpit.
