hi, AMC cars, including Eagles have very few weak spots, from an engineering standpoint. The most famous(infamous) one is the 81+ plastic valve cover, second, to some, is the vacuum disconnect front axle, easily fixed, third, is the two piece rear axle, not a real problem in the real world, IMO, and fourth, and little known, is the rear leaf spring hanger assembly/mounting point. This is a piece of stamped sheet metal, nothing more. The stamping gives it it's initial strength. You have your trunk pan, flat sheet metal, then you have your rear leaf mounting point, a curved, (Kind of like a soap dish) piece of stamped sheet metal tack welded to the trunk floor pan. This is initially very strong, due to the stamping. BUT, if over time, ANY small leak between the two pieces of sheet metal occurs, and water gets up in there, you now have a perfect (soap dish) container to hold water. And once water gets up in there, it's (sooner or later) game over. The rear leaf spring mounting point will rust through, from the INSIDE, and will look good to you until it fails, and the rear of your leaf spring pops up through your trunk/hatchback floor. This is the point most people can't deal with, and the car is either parted out or junked. And yes, this actually happened to me, on an 80 Spirit., many years ago. So, on my next car, my 82 Eagle, I was aware of this, and watched the rear mount carefully. When it started to look weak, I had 1/8" steel plate welded in above the mounting point. Didn't "fix" the problem , rust was still there, but kept the car alive for another 6-8 years. There are a few ways other than mine to get around this, as other listers have demonstrated , but this was mine. Just a heads up, y'all! and btw, this is not just Eagles, but ALL small body AMCs. The Eagle "Unibody" was advanced for its time, but instead of sheet metal over box section steel,it was basically sheet metal wrapped over sheet metal, two, sometimes three times, as in the front sub frame, and once ANY water gets between the sheets of metal......well..they swell out, weaken, and die. This is why any kind of frame repair on an Eagle is so difficult, and expensive. I am not new at this, but even I, after all these years of AMCs can get fooled. My current AMC project, 84 Eagle sedan, when I bought it a few years ago, I crawled up and under it with a flashlight and a hammer, beating on frame rails, listening for the "ring" of solid steel, looking for soft spots. Looked good bought the car. Fast forward to this year, motor out, off to machine shop, see a small, less than two inch rust spot behind and under upper control arm, engine bay side.investigate further, the spot under upper control arm,another perfect little"soap dish" area to catch and hold water was rusted through, not much, less than 1/2' BUT, ALL THE WAY THROUGH.. So, water has been getting into the drivers front frame rail for who knows how long Investigate further, and about 80% of the drivers front frame was rotten, again, from the INSIDE, looked great from the outside. Anyway, I'm lucky to have a good fabricator available, and he replaced most of the front frame rail. Remember, this is not square section steel, but 3, "THREE" layers of sheet metal wrapped around each other. Cost me a cool G, and I was happy to pay it., having so much more in the car already. The Passenger side was/is thankfully ok, or I might have had to pull the plug on this car. Ok, I hope I have not bored anyone to tears, long story short, Eagle#2 will live! Moral of this story, rust never sleeps, so y'all keep an eye out! Peace, gz