Suitable for SDV?

Sent an email to Westfield asking if the 1998 model was suitable for the SDV (it only say pre 1996 in the literature). Their reply was: "We can supply a kit to use both pre and post 1995 Mazda MX5’s. If you want to use the post 1995 car then you will need to upgrade to a cat exhaust silencer." Not sure how much that will cost, will find out later!