They're already in the BTCC with the ZS touring car, which didn't do to badly. Why enter the ZT? I expect the reason that manufactuers don't enter Skylines and V8 ZTs and such (apart from money) is the regulations probably won't allow them.
Was that aimed at me?
If so, I think they're changing series, because the SCV8 will cost them a lot less money, as there are pretty standard chasis etc. as well, it means they don't have to put much work in so they only really have to submit the sillohuette body's . Well that's what I thought anyway.