I love those slantbacks! Great design. One of the best parts about those cars is there are still SO many parts for them (just don't break that rear window!). GM made a TON of them, and most items from 77-90 swap over, and salvage yards are still full of them.
My best friend in high school was given a nearly perfect but BORING 50K mile '78 Impala 4dr, silver over red vinyl, when he got his driver's license. Other than power steering, brakes, and a/c, and the 305 V8, it was a stripped model, even had the single speaker AM radio.
That car taught us how many parts would swap over between models. We hit the salvage yards hard.
We put in Caprice wood center dash trim with Delco cassette stereo, a Caprice dash pad with dual speakers, ran speaker wire to the rear deck and added speakers back there. Then the plain bench-seat vinyl interior came out and red Olds Delta 88 door panels with wood trim and pull straps along with red Buick LeSabre Limited cloth seats went back in. The plain sun visors were replaced with Buick ones that had lighted vanity mirrors. The block off plate in the center of the dash was removed and a Caprice electric "rolling" digital clock went in. The fixed steering column was replaced with a tilting column from a Caprice, with the fancier Buick chrome shift lever and turn signal/tilt levers added, and the very plain base-level Impala steering wheel was replaced with one from a Celebrity Eurosport.
Once done, the inside was a mis-match of all the GM divisions, but the colors all matched, and we installed Chevrolet and Impala emblems on anything that said Olds or Buick. It was a real mutt but looked like it could have been factory.
On the outside we blacked out the grill and the recesses around the headlights, and the metal panel around the tail lights, added Rally wheels with Eagle ST RWL tires, installed Caprice GM "bullit" door mirrors, and added black SS decals to the front fenders and trunk lid. To us, it looked mean. Later on the 305 was yanked and swapped for a 350, and the car really ran. But sadly the rust finally took it. Still it taught us a lot about how GM cars were just pegboards for adding options!
Fun stuff!
-Mike
You can see Laird's Impala in the background here. This is around 1990
My goofy buddy Frank acting dumb while I'm doing what teenagers do with my then-girlfriend, and you can see my Chevy Citation X-11 and Laird's '78 Impala in the background. Like the SS decals on the fender?? We beat GM to an SS 4-door! This was 1992! Ha!