Just to throw this out there but have you looked at getting Todd's (DaVinci) designs caster plates? He made a few extra and I just put a deposit on a set for me a few weeks ago. I would HIGHLY recommend them as all the track oriented RSX's over on clubrsx use them and have nothing but amazing things to say.
Also a member over there has the front PCI bearings that press into the front LCA bushings and those add more caster as well. With our type of suspension the more caster you have the better! Caster = more dynamic camber during turns!
EDIT: I just read your last post! Doh!
If you need to save that travel why not look into a quality coilover that uses the body of the shock to lower and not lose shock travel such as Zeal or Bilstein? Not saying that your Koni/GC setup isn't quality, by far it's one of the best setups without having to spend 3k+ on a coilover.