Neil - you take things too seriously it is not like I am going to be any competition for you.
I have had some good discussions with Brad on a cage design that involves welding the usual mounting plates into the car but with the addition of captive nuts to bolt the bar work to. The main loop and rear legs are legal if you change the registration to a two seater. The bolt in design allows the front bar leg and door braces to be removed for registration purposes.
Looks like I am just going to have to add an few more springs to my current collection of 3-4 kg progressive, 4 kg, 4-5 kg progressive, 5 kg, 7 kg, 8 kg and 12 kg until I come up with something that suites what I am attempting to achieve and actually works.
I should not bring up the question of rims then as I am some what of a wheel whore.......