Check the number of threads on the shock nut on the one that went bad and you just replaced. You should have 5 threads showing. If the one you took off did not reach the shelf in the shock stem, it will go off in a hurry. As for the height, not a big deal, but all I have seen had at least one of the fiber spacers under the white spring seat.
If the installers just tightened everything up after getting things in place before taking it to the ground, then nothing was in a neutral position, all the rubber bits were in a slight twist and have remained there through the 10K miles, lots of stress on all the parts concerned. Best way of course is, snug all nuts up, then putting it on a rack after driving the car around the block a few times, then torque to specs on the rack. Alternate way, after getting things in a settle position, slightly jack each tire up to clear the ground, I take them off, then torque to specs.
Have a look at the other side, the old one, bet the large donut is thin. Might not be even wear either, one thin side.

 

Motorcarman, I just checked the rear ride height and indeed the passenger rear (15.375") is .5" lower than the driver rear (15.875"). This compares to the spec of 15.94" height for the rear. Since my problem in the front is that the driver front (15.25") is .5" lower than the passenger front (15.75") this reflects your statement about the rear affecting the opposite front corner. So, this opens a new avenue for explanation.

 

I remember many years back taking the rear shocks and spring assemblies out, and when I put them back in, a wiring loom managed to get under my driver's side upper mount before I noticed and tightened everything up. It did raise up that corner a bit. Look closely up there.

 

cjd777, on the mount that was replaced, the shock nut had 5 threads showing on the mount plate. The same shock mounted to the new mount is showing 6 threads. I doubt very much if the original installers settled in the shock and mount replacements and then retightened. The shocks and mounts (both sides) were replaced when I acquired the car in 2018 because the mount plates were original and were in dire need of replacement (no one mentioned needing springs at this point). It was two years and 4,000 miles later that the springs were replaced (five years and 10,000 miles ago) in 2020 due to ride height being only 14.5" driver side and 15.0" passenger side and affecting tire wear and handling. The shock was still centered on the mount during those two years. The new springs brought the ride height to 16.0" driver side and 16.5" passenger side (that same half inch difference throughout the progression) but within 50 miles the mount plate/shock nut had already started drifting away from center. Of course, over time, during the subsequent 5 years the ride height has dropped to 15.25 driver side and 15.75 passenger side (see July 2nd "Follow up" post.

 

H2Oboy, thanks, will do.

 

Just a thought: The original white spring supports are only slightly wedged, to match the flattened bottom of the original spring. All the aftermarket springs I have seen have unflattened open ends and require the matching new mounts (with an increased wedge). - see ardinesh example. If new springs were fitted with original mounts, there would be a mismatch in wedge angle and result in offset loading, similar to having the wedged support in the wrong rotational position.