yes
in the lamp assy. Mercury switch
yes front coil springs with front shocks on a 1987 cadillac brougham rear wheel drive
They are commonly referred to as filler panels.
a fuse, relay, bad ground or positive wire at switch or solenoid, etc.
at least on a 79 fleetwood it is located in the light switch itself
20
Not without modification
where is the starter to begin with
4" round in front and 6x9 in back
Contact a GM dealer and see if they can make you a copy of the keys from the VIN. Otherwise you may have to call a professional locksmith.
Try e bay.
Try the repair tips on the Autozone web site.