guys how did you go about connecting the stock head unit to the amps?

I only just purchased my CL9 and coming from a civic where i had a DIN headunit and full system 2 x amps 2 x 12 inch subs and 4 x 6 inch splits I am real keen on getting some of this gear into my 05 CL9.

Ive seen the double DIN modification , is what you all are using? (i dont like the idea of having 1 redundant unit in my car) Anyway to add an EQ to the stock head unit and some kind of connector that adds RCA connections to the stocky?

Really appreciate any info on this.