I recently started a thread on adjusting the steering box on my 1987 560 SL. It can be done with the box in the car, but it's not the easiest thing to do. And no, I didn't have to take the exhaust manifold out. What I did have to do was remove the heat shield on top of the exhaust manifold; two screws. Along with that I had to detach what I believe is the exhaust gas recirculation valve to get to the second heat shield screw. Once that's done, get a 19mm crows foot on the end of a universal joint and long 3/8" extension. This will allow you to break the nut loose. To adjust the screw, buy 6mm allen wrench with a ball end (as long as possible), cut the right angle (non-ball) end off it and slide it into a 6mm socket. You can then hold the lock nut with the crows foot while turning the adjustment screw with the allen head. To tighten the steering box, turn the screw counter-clockwise. By the way, I bought all of the necessary tools at Sears for less than $ 25.00.

Hope this helps.

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M. Sandler

1986 560SEC: 150,000 miles, runs great, but I've got to sell it (too many cars for one man)
1987 560SL: 122,000 miles, used to run poorly, now (thanks to forum), runs great!
1997 GMC Jimmy: Turned out to be a turkey.
1989 T-Bird Super Coupe: 150,000 miles, still runs great. Ford got it right.