Not only does the Linn sound poorly when improperly set up, it doesn't take much to put them off spec. The Sondek is perhaps the most finicky turntable on the audiophile market
The inner platter should have had something wedged under it for transportation… to stop the bearing point from damaging the surface of the inner bearing
Weld a spindle to a steel bar about 15" long. Use that to jemmy the main bearing housing to correct the off level wrt the sub chassis. Thats what they did in the factory. Not kidding.
Never heard of that, not idea as the stress may damage the lining, the hollow adjustment bar that Linn supplied/recommended slid over the housing to avoid such damage.
I have a LP12 which I no longer use and if I sell it its going to be collection only. Its has a Ittock arm the vertical bearing was sticking in one spot I used some lighter fuel and that cured the problem. It leaves a small deposit of grease behind I purchased the LP12 in 1980 second hand for £300 with the Ittock arm and Linn Valhalar board.