front output or rear output pioneer deh p4400

[Mr.350]

Ok i have this exact headunit (http://cgi.ebay.com/Pioneer-DEH-P4400-Car-Stereo-XM-READY-CD-R-CD-RW_W0QQitemZ260045494146QQihZ016QQcategoryZ39762QQ rdZ1QQcmdZViewItem) and i was wondering since i already have a sub and amp connected to the what i call "rear outputs" which are the rca's fixed into the radio, if i wanted to hook up my new 4 channel amp, whould i connect it to the front outp or just hook the 4 ch. up to the rear output and then use the line out of the 4 channel to go to the mono? i very confused here, and i just want to get the best out of my recent purchases so any help would be greatly appreciated.

[Synthetic]

Are you wiring door speakers to the 4-channel? I'd run the front door speakers to the amp's front channels and bridge the rear channels for the subs. You'll need to connect both sets of RCAs from the head unit to the amp.