1993 Cadillac deville sedan 1986 cadillac deville RIP
with a bose system you have to rewire the cars audio its not that expenisve you just have to replace the wireing that goes to the factory speakers to bypass the internal amp. also your wiring harnes question crutchfield.com sell a wiring harness to you when you buy a radio from them but their stuf isnt always cheap. your other option is ebay they sell indash kits the will fit your car no problem also if you decide to wire the whole system up get a 4 channel fron the frnt/rear and a seperate for the subs. your other option to wiring the radio is to splie the factory harness into the new radio . its the easy but complicated way just make sure you do one wire at a time. but if you do the reiwre option you have to only splice 5 wires power, memory wire, ground antenna and lumination. on my cadillac i rewired the whole radio and just used the wires i specifed periously, and ran all the speakers wire to the trunk whree i have 3 amps. good luck.