Do what Ferrari does to keep track of good clients, prioritize some but randomize the majority, and actually match production with demand. The latter is the biggest issue. There would be little to no premium if you said "Everyone who wants one will get one in a reasonable amount of time." Sure, some would pay to get it sooner rather than later and eventually production will stop, but if people can get cars with ease, there will be little to no premium.

Go a step further and say if ownership changed when it came in for service prior to two years, you'll never get another one and therefor that dealer will potentially be hurt as well.

It's really not that hard. Porsche just doesn't care. Porsche can engineer cars like the 918, but they can't figure out how to allocate some special editions? Maybe Porsche should talk to the VW emissions team on finding a creative solution...