Coil Spring Adjusters??

Those are the clamps that pinch two coils on the spring together, or spread them apart, right?
They're total crap. They're fine for some homeboy to put on his '81 Grand Marquis, but for a car you care about, stay away from them!

The coil springs are engineered to work as a complete unit. When you cut a coil off to lower the car, or use one of these clamps, you place stress on the spring that it wasn't meant to handle, and it won't work as designed. If you're lucky, only your handling will get messed up. Those clamps are famous for causing broken springs.

No, the shocks and struts will work fine with shorter springs. The factory struts are actually fine for street driving. Some people like to upgrade them too, but you wouldn't notice the difference unless you were on the race track.

If you lower the car 1.5", you might need to get caster/camber plates. They are installed on top of the strut towers, and increase the range of adjustment for your front suspension. Depending on the alignment shop, 1" drop seems to be the limit for them to get the steering back where it should be without c/c plates.