Lars:
It is true you guys have some limits (boo hoo :( ) on what you can do with the 76 and 77 cars, but you have an open checkbook opportunity for the 74 and 75 cars. Here are 2 on ebay right now...Freddie Hernandez's beautiful 74 for $60k, and a 75 Carrera for $35.9k.
http://www.ebay.com/itm/Porsche-911-...US_Cars_Trucks
http://www.ebay.com/itm/Porsche-911-...US_Cars_Trucks
My 77 is a blue plate CA car and was licensed through 2015, but will never be registered in CA again (most likely) with the 'delete options' I have incorporated. These cars will most likely not take off in value like the long hoods, but as indicated in the Excellence article, their increasing value will allow a guy some room to install some of the 'factory bits' that make them much more fun without getting upside down. And, like the 964s from 4-5 years ago, they are still relatively inexpensive for a 35-40 yr old iconic 911 that was built during Porsche's hay day in motorsports.