Would it be possible for me to install a set of Mistu Evolution, Skyline or Even an RX7 4 piston caliper on my GSR...what modifications would have to be made...?

 

Why do you want to install those calipers specifically? I'm new to Hondas, but own an Evolution and I'd say it would take quite a bit of fabrication work to fit those onto an Hcar. Why not consider an aftermarket braking kit for your specific application instead? Is this modification for braking performance, or for "bling-factor"?

 

generally the takeoffs of those cars are WAY cheaper then equivalent aftermarket parts. I can pick up STi brembos for 500 a pair with rotors easily...