1997 After-market Stereo Wiring Trouble

[fury_vvulf]

I purchased a 1997 Thunderbird that already had an after-market head unit installed. I attempted to upgrade the head unit to a newer model (since the previous one didn't play CD's any longer). After removing the previous stereo and wiring in the new harness for the new pioneer head unit, several issues occurred.

1.No power to the head-unit is present.
2. My remote will still honk my horn, or turn on my interior lights, but doesn't operate my trunk release latch or my door locks.
3. The power locks no longer work via the switch, nor does the trunk release.
4. Cruise control is no longer working.
5. The electric switch that goes from brake to Automatic Transmission solenoid is no longer functioning (so i can't shift my car into gear).

Obviously some serious electrical issues are present...i have checked the fuse panel, and all fuses are in tact. Ignition is still possible, and power is getting to the rest of the major systems. any idea what could be causing my issue, or where i should begin looking to pinpoint the problem? any help would be greatly appreciated. Thank you.