Ownership update: our office had everyone work from home during the omicron surge, so it's taken until this month to get up to 184k miles, at which point the car told me it needed another oil change.
For the most part, the car has been trouble-free, though there have been a few small issues that I hope I addressed today. The most serious was that the car would occasionally stall at very low speeds in first gear. Sometimes it would go months in between, but a few days back it happened several times in one day. It never failed to refire, but it wasn't ideal. I replaced the cam and crank sensors, which the Lincoln boards indicate are the most likely culprits. But we'll see.
Changing the cam sensor is easy; it's right behind the power steering reservoir. Changing the crank sensor is a bit more involved, as replacing it requires moving the AC compressor out of the way, and it's a bit hard to get at. So I figured if I had to remove the belt, that was the ideal time to deal with the other problem, which was a small coolant leak right directly below the water pump. The good news is the Ford mod motor makes replacing the water pump the easiest job in the world. It's held in with four bolts and sealed with an O-ring. The old water pump did look as if it had been leaking from the O-ring. Old one out, new one in.
At the same time I decided to replace the coolant crossover tube that connects to each head and the coolant outlet hose and thermostat hose (the thermostat arrangement on the Mark VIII is goofy). The car's crossover was a bit rusty and I wasn't sure I'd be able to get the bleed valve off without stripping it. Ordered a used crossover on ebay (only source for them, sadly...no telling how many I've walked past in a junkyard not knowing I'd eventually need one), a new bleed valve and a new O-ring kit. Put that all together and installed it.
While doing all this I saw that I needed to replace the belt, too. That's a bit harder than it ought to be on this car because the 97-98 Mark VIII EGR system is, like the thermostat arrangement, goofy. Part of the EGR basically lives inside the recess of the crank pulley, and there's a bracket that bolts to both sides of the pulley.
You can cut the old belt to remove it, but the only way to get the new one on is to remove that bracket. Not impossible, but you'd be cursing the Lincoln engineers if you were doing this on the side of the road after throwing a belt.
Got the new belt on, filled the coolant, let it warm up and now it's cooling. I've heard horror stories about bleeding the air out of these cars, but the factory service manual makes it sound like a non-issue. Guess we'll see on that, too.
Long-winded way to say that aside from some minor issues that shouldn't be too shocking on a car with this many miles, things are going fine.