Thanks for all the comments and welcome, I've arranged to get the car properly sorted, seems a good plan.
I've not had the Porsche long but my initial reactions in comparison with the Caterham 7 are as follows...
The 911 is a much bigger and heavier car, the Caterham with a 10" steering wheel and no power assistance is outstandingly agile and with little space between yourself and the cockpit, you are [as on a motorbike] very much part of the vehicle.
The 911 is much more substantial, refined with more than sufficient performance for the road. Extremely comfortable [and waterproof] and with the roof dropped by pressing a button! fresh air motoring is so easy.
The Porsche is a 'pussycat' round town, docile, light and controlable but readily transforms with a few revs. I'll be taking it on a trackday [soon I hope] which will give me a better chance to explore it's potential.
One aspect of the 911 I hadn't fully concidered was other peoples attitude. The Caterham certainly turned heads and attracted interest in any French or Italian town or ville and older women in this country seem nostalgically attracted [to the car not the driver] but there is sometimes [obviously in retrospect] an anti 'rich ba*****d' attitude to the 911.
I'm still grinning!
Ian