I can't find the procedure on the service CD, but it does note that this area changed for the 1988 model year.

"The control valve in the vacuum line between throttle assembly and exhaust gas recirculation valve is no longer required as of 09/87. The exhaust gas recirculation valve is connected with vacuum directly only as a function of the thermovalve."

So it makes a little bit of difference whether your 560SL is 86/87 or 88/89.

__________________
Mike Heath
1988 560SL Black/Palomino
1988 300SEL Black Pearl/Burgandy
1984 500SEC Anthracite Grey/Palomino