the best location for the antenna is going to be in the upper left corner of the windshield. inside of course. you'll only need to cut the thicker wire as its the primary. this should help a ton: this is the diagram for a remote start for the 05 camry from directsoft. this is the program i use at work when i install a remote start.
12volts

white/red (30A), white (5A)

+

ignition harness
Starter black/white + ignition harness
Second Starter black/yellow + ignition harness
Ignition black/red + ignition harness
Second Ignition black/yellow + ignition harness
Third Ignition N/A
Accessory blue/red + ignition harness
Second Accessory N/A Keysense blue - ign harn or BECU, top plug, pin 19
Power Lock blue/yellow - DKP or bottom of fusebox, 20 pin plg
Power Unlock blue (double pulse) - DKP or BECU, top plug, pin 22
Lock Motor blue/red 5wi DKP or bottom of fusebox, 13 pin plg
Unlock Motor blue/black 5wi DKP or BECU, bottom plug, pin 11
Parking Lights+ green + DKP or bottom of fusebox, 20 pin plg
Parking Lights- red - switch or BECU, top plug, pin 8

Hazards lt. green/black - switch or BECU, middle plug, pin 10

Turn Signal(L) green/white + turn signal flasher relay in DKP Turn Signal(R) green/yellow + turn signal flasher relay in DKP Reverse Light red/black + DKP or bottom of fusebox, 20 pin plg
Door Trigger see notes - see notes
Dome Supervision green/red - ignition key cylinder light
Trunk/Hatch Pin green - DKP or BECU, bottom plug, pin 6
Hood Pin black - theft deterrent ECU behind glovebox
Trunk/Hatch Release white/blue 5wi DKP or BECU, bottom plug, pin 12

Power Sliding Door N/A
Factory Alarm Arm arms with lock
Factory Alarm Disarm disarms with unlock
Disarm No Unlock use key sense wire
Tachometer black/orange ac ECM behind glovebox

Wait to start N/A
Brake Wire green/white + sw or bottom of fusebox, 20 pin plug Parking Brake red/white - parking brake switch
Horn Trigger green/black - sw or bottom of fusebox, 24 pin plug Memory Seat 1 N/A Memory Seat 2 N/A Memory Seat 3 N/A