So if it's a wide body already the wheels are the same dimensions, unless you change something with the geometry i.e. offset/ back spacing or a-arm lengths. When you say a campi clone do you mean a wide body campi clone or a early style narrow body wheel to fit the wide body?
The wider the rim the deeper the dish, more shiny metal surface you can have polished so it's a personal choice I think, whether you want it to drive or look good in your garage. Wide body (10 spoke) campi clones will be 10" and 13" width with standard wide body offset unless you get a set custom made.
Looks are one thing drive ability is another the wide body cars are renowned for tram lining, if I was getting a custom set of wheels made I would fabricate longer a-arms (like the Si had) and push the wheel center further out for a much better driving car.