I've had some serious systems in the past, but am running a sad setup right now. I have an 06 Dodge 2500 MegaCab. It has the infinity 7 speaker setup but it's pretty awful and two speakers are starting to buzz a bit.
I upgraded my headunit to a nice kenwood nav unit (DNX9140) a while back but left the factory speakers and amp. I would love to have a sub but can't have one as I am not willing to sacrifice any space. On a regular basis I use the toolboxes behind the rear seat, store rifles behind the rear seat, and fold the rear seat down for large cargo. This eliminates under or behind the rear seats. I have an inverter under the DS seat and will put an amp under the PS seat, so the amp needs to have a relatively small footprint.
I plan to use a 4 channel amp and will be putting 6.5 coax in the rear doors and then either 6x9 coax in the front doors with tweets in the dash OR 6x9 coax with 3.5s in the dash powered from the head unit. Not looking to mod any panels.
I've been looking around a bit and had semi settled on an Alpine PDX-4 amp and either Alpine SPR or Polk MM coax speakers and whatever 3.5" speakers I find. I will also deaden the doors while I have the panels off.
I haven't been up on speakers in a long time so I would appreciate any thoughts or suggestions.