by crossovers I assume you have the passive x overs

ie

then its just head unit --> amp via rcas ---> amp to speakers front channels, to the input sid eon the x over, then tweeter to the tweeter side or somehting similar, 6.5's to the woofer sid eor somehting else similar.

then 6x9's to the rear channels

unless its a 2 channel amp, then youre gonna have fun.