Either a 368 cid gas V8 or a 350 cid diesel V8.
~4,200 lbs
Rear
5x115
The blower motor relay on a 1980 Cadillac Coupe Deville is situated on the passenger side. It is located in the vicinity of the firewall and is just below the windshield.
Firing order for 1980 Cadillac Eldorado 6.0 Engine is 1,5,6,3,4,2,7,8.
It appears your blower motor is not working correctly on your 1980 Cadillac Coupe Deville. The vents are for both AC and heat. You may also be losing vacuum pressure. If you cannot find the source, your mechanic can help you do so.
Google Kelly Blue Book and enter in the information such as condition and mileage, it's your best bet for an estimate
What size engine?
0.35 gap
I got my fuse box daigram at Murrays' I bought a Chiltons Book for my 1989 Coupe Deville. It lists previous years also. You can probably have someone at Murray copy the diagram for you out of the book. They copied some things for me.
Depends the model of the Cadillac. A 1980-1985 Cadillac Fleetwood Brougham coupe gross weight is 4000lbs.-4400lbs.
The first thing you should do is loosen the four nuts bolting the seat to the car. Then you can tilt the seat back and disconnect the wire harness from the motor, and finally manuever the seat out of the car. Installation is the reverse.