This is an install I did on a buddies pickup last summer.

Head Unit-Sony CDX-GT660UP
Front Door Speakers-Component Rockford Fosgates PRIME R1652-S
Rear Panel Speakers- Rockford Fosgate Punch P1462
Subs- 2* Rockford Fosgate R2D2-12
Amp-Kenwood KAC-8105D
Amp Kit- Db Link 4 AWG
Underseat box with minimum modification

Youtube Video of install.