ara,
Two different series cars we're talking about. Lotus brought in somewhere around 50 or so Sport 190s, these were set up as track only cars with roll cage etc. Had the higher tune Rover engine. These are legal for track use, although some owners have been able as limited use vehicles which are restricted in the mileage they can do.
Then you have the Sun international cars (Honda conversion) we have a guy on here who has one, he can probably address this car. I believe SUN is no longer in business??
We actually have a third group. These are euro cars that wer brought in by individuals (one particular guy sold several on ebay before getting nailed and I think put in prison). One fellow used to be on the list bought one. After lengthy appeals he was given a specific time period to sell the car overseas or face having it crushed.
Prototype Racing does offer a conversion for elise to Honda power, a bit pricey, and lots of controversy surrounds this conversion in UK.
CHris