I'm having difficulties sifting through and finding out exactly what I can reuse from my old system and if it'd be worth it.

I have a pair of Kappa Perfect 6.1 Components w/ crossovers(6.5), Kappa 6.5 2 way coaxial and Kappa 6x9 2 way coaxial.

Also have a 1 channel 600 watt rms D class Infinity Reference Series Amp and a 4 channel 75x4 watt RMS Infinity Referene Series amp.

Can these speakers be used in my 3GS with ML?

And if they can be used do they far exceed the performance of stock?

I really don't want to replace the speakers i plan on selling everything (except those Kappa Perfects, they're amazing)

Haha, i have the same setup (infinity perfect kappa) and wonder the same question on an ES350 with ML.