Hi and welcome from Australia
great looking Zed you have there.

Hi mate welcome, your car looks great!
Bilstein didn't do any coilovers. If I was a betting man I'd say they're Bilstein B12, in which case the springs will be Eibach Pro which can be bought separately. Usually the dampers go before the springs
What you have described sounds like the standard set up, some people have fitted coilovers to the rear but I have no experience of them. There are various aftermarket springs and shocks that can be fitted.Follow up, still getting used to the forum...
Have just been reading other threads and my rear suspension is a shock with seperate spring beside, does this mean I have coilovers front but not rear? Certainly have bilstein shocks of some sort front and rear and I'm 99.9% sure the fronts are coilovers, but now questioning the rears.
Can anyone tell me what to look for to confirm setup? Thanks again and sorry to those of you who sees this as obvious.