After I filled the rear with 80W-90 gear oil mixed with a can of Motorcraft XL-3 friction modifier I took the car up to Scholl Canyon where I know the only parking lot around that is usually empty enough to do some figure 8s. Absolutely no noise from the differential! There is some whining from one of the bearings I think. When I replaced them a couple of years ago I could only find one Timken bearing on short notice and the other one was some cheapo brand. I'll have to investigate, but for now it's not a big concern.
The neutral safety switch is still leaking, so I ordered a NORS one on ebay for 65 bucks. I bought a newer, 3-prong one for 8 bucks just for the gasket, but apparently they don't work with the early 904s.
Anyways, when I testfitted the "new" deck lid I noticed that it wasn't closing all the way, which the current one also did, but I thought it was because it was all bent up. I ordered new "marshmallow soft" Y-profile weatherstripping from Detroit Muscle Technologies, because what was on there was the wrong style.
After I removed the old weatherstripping some paint had come off with the glue and some paint had been scraped off by loading stuff in the trunk.
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I hadn't really thought about that and thought glueing it down was gonna take an hour max. If I didn't paint it now it would have been tricky and messy in the future. So yeah, scraping, sanding, priming and painting took all afternoon.
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I let it dry for 24 hours. I used the 3M Super Black Weatherstrip adhesive. Steele Rubber has some instructions on their website. They said to spread a thin layer on both surfaces with a popsicle stick and let it get tacky and then add some more on one side and press it down. It got tacky so quickly that spreading it wasn't really working. So I just spread it right out of the tube and I think it worked well. The clothespins weren't really necessary - just added insurance.
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Once it's pressed down you can't adjust anymore, so it's not perfect, but good enough.
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The lid (latch) still needs some more adjustment, but it's already way better than before. The latch could probably also use some lubrication. And on the hinge side it's also sticking up a bit. Here you can also see why want to replace the lid...
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