Thanks for the reply. Yes, I'm endomorph/ectomorph with a long body, but most of all I'm getting to old to sit like I'm in my old Sports car in the recline position! :) The big problem is that their is very litte support at the base of the neck which causes a droop of the shoulders, a leaning neck, and voila, sore neck and back muscles, no matter what the position or height. I understand why the forward lean but any neck support following a 30 degree curve of the neck during impact will suffice. Its simple really, put one post in a vice at about the point of it lowest setting on the seat, bang with a heavy hammer or sledge until you get a slight bend, switch posts and wack it once or twice until it matches, re-insert and test. Always feels better, allowing better posture. Another way is with a pipebender and vice, what ever works.
I have noticed that the Lexus posts are thicker than most, might take a little extra work, but it's do-able.
Update: After searching a few times this seems to be the trick. Its for a LS F1, does anyone know if its the same on the LS460L?
"Have not tried this yet, but after more searching on the web, I found a post in another LS F1 forum a procedure that worked and that actually makes sense if you read the instructions and view that picture in the service manual. What the fellow did was to run the headrest all the way up with the switch, then he pressed downwards on the two plastic surrounds of the metal pillars that support the headrest. This presumably releases the two clips inside the seat that retain the two rods. The downward arrows in the manual picture actually point at these plastic surrounds, so it makes sense. The text is a bit ambiguous. I think this another example of poor translation of a Japanese manual by a person that either was not great at English or Japanese or was not really sure what the Japanese text meant.
Just did it and it was extremely easy."
(Update: Incorrect instructions. See further posts)