Guess I'll be on the blower tomorrow....
Don't bother phoning. All lines lead to some bint in Swansea who's a useful as a used condom... You get the picture.
Turn up with the docs, or get the form from the Post Office and send it in.
Speaking of.. What is the deal with the emissions test for a kit car? Clearly you can't exactly test it 'per the book' since it isn't in the book, so do you get an engine-age related test, or the non-CAT test?
You have to prove the age of the engine. If it predates August 1995, Non-cat limits apply (3.5% CO, 1200 HC). After that it gets a BET (0.3% and 200HC..?). Technically if it gets a Q plate or is "Amateur built" it's visible smoke only though, although they are getting clever and logging emissions limits with the registration so they pop up during MOT.
So, IVA it with an old nail of a 1994 engine, then do what you want after that.

Kevin