Anyone changed rear springs in a BA before?

I was wondering if anyone had changed rear springs in a BA before? Sedan, not crappy solid-rear-axle ute/wagon garbage. (
to all the F6 owners out there)
Do they run struts in the rear? Or is it still a seperate coil/shocker arrangement?
Mate I work with wants to lower his and I have no idea what's involved. Fronts are easy. Rears are probably easy too. Any info appreciated.

Do they run struts in the rear? Or is it still a seperate coil/shocker arrangement?
Mate I work with wants to lower his and I have no idea what's involved. Fronts are easy. Rears are probably easy too. Any info appreciated.