Hello akaNSX, I am Japanese and live here in the UK (London), I have a business that import cars from Japan to the UK. So I guess I can help you here.
You can get the conversion done in the UK after importing, so there is no point in buying the parts now.
Will you be importing as a personal import (no import duty/tax)? Or commercial (you have to pay duty/tax)?
To qualify for personal import, you had to have lived in Japan for the past 12 months, and owned your NSX for the past 6 months. Otherwise you will have to pay duty. That is 10% of (CAR COST + SHIPPING) and then 17.5% on top of that. (Approx 30% of CAR COST + SHIPPING)
Shipping probably cost around 100,000 Yen.
Amount of modification required depends on what year your car is. If your car is going to be more than 10 years old, then you only need to pass the MOT here (equiv to Japanese Shaken). For MOT, you will only need to add rear fog light. This can be done by changing to UK style fog lights (it has to be from rhd drive country, so get the parts from here), or stick an after market one at the back. Or you could just colour one of your reverse light with red vinyl.
If the car is less than 10 years old then you will need to do the SVA test. Which will require you to change the speedo to read in mph and change the fuel restrictor. The parts for these are available in this country.
If you are coming here with the NSX and taking the car back with you within 1 year (was it 6 months) then the procedure is different, so let me know.
If you didn't understand any of that, email me in Japanese. (
[email protected])