Reconciling volume/gain between interface, Sonar and Plug-ins

I've been trying to be very diligent with my gain staging lately, but have run up against a major issue. Here's the scenario.......
 
Recorded a couple guitar tracks peaking around -12dB or so on the faders. I'm using Amplitube for my guitar plug in the FX bin on each track. Levels on the meters of Amplitube seem ok. Recently bought a couple Waves plugs (Eddie Kramer Guitar, CLA pack) which I have on my Guitar Bus. The problem is, the signal coming into the plug-ins is not strong enough to get the plug anywhere near the optimal level for effective processing. If anyone uses these plugs, there's a light that turns green, yellow, red, indicating optimal input, yellow being the best. I'm not even getting to green, with the input cranked! And the volume coming from my speakers is very loud. And if I tweak one knob on a plug, or adjust a fader, it effects everything else in the chain. Very frustrating!
 
I've tried normalizing some tracks down a few dB, then raising the gain or fader, or input on the plugs, but it's just turning into a vicious-cycle mess.
 
So, I guess my issue is how do you guys reconcile volume/gain between the interface, Sonar, and plug-ins? It seems like a very difficult balancing act to get everything on the same wavelength, so to speak.
 
~Jeff