had the same problem the other day with a mitsibushi fto
the lad had put on a stainles cat replacment pipe on which obviously wouldnt pass the cat test. then we worked out that there was no listing of it in the book so it became extept from a cat test and acording to the test procedure you then just carry out a non cat test.
so id think with yours not being a std car it is not going to be listed ethier, so should qualify the same

(but im not an mot tester just work at an mot station)
and of the top of my head im sure its any car after 1992 should have a cat