Hi Guys (Especially Malc!) - Found this post on the USA L.O.C. website, and I intend to try this when the weather settles down (my LS400 lives outside!).
It was suggested as a cure when the u/s revcounter needle sits BELOW the zero mark, but may work in other circumstances.
1. Remove instrument cluster (and I'm hoping I can leave it connected!)
2. Remove front transparent cover.
3. Gently grasp r/c needle and pull out till a 'pop' is heard, or felt.
4. Rotate needle CLOCKWISE till similar 'pop' is felt, then gently release needle.
5. Push needle ANTICLOCKWISE to align with Zero mark.
6. Test by pushing needle to, say, 3000, and release, and it should return to zero - If it does, HAPPY DAYS, it should now work after reassembly.
U.S.A. site feedback from at least one guy indicates this idea is a go-er, but then I guess we have nothing to lose by trying it.