hi guys, getting ready to put more bass in my 98 323is, was wondering if its a easy job. i have two 10' JLw6 subs and a rockford fosgate 500a2 amp. if i were to keep the stock radio, do i need to get a rca converter or do they make some kind of special harness for it. i might be changing some of the speakers on it also, does anyone know what size all the speakers are. thanks for the help.