1986 560SL with M120 V12 Engine, 1988 560SL Stock
I never got one of those rubber boots off without tearing it. Of course the new ones are nice and pliable.As requested, here are some photos of the upper to lower manifold seal area. The access is a pain but I don't think replacing them is hard. The hard part is getting the manifold off and making sure you don't break anything in the process. That makes it a two day job for a home mechanic and that is if you have all of the gaskets and seals ready to go and no other complications as in my case(broken bolt). I am by no means a 560 CIS expert, as this is my first one, but I think those seals are usually not the prime suspect when it comes to air leaks. My 1975 has it's original ones and I have no leaks. My first and waaay easier target would be various hoses and then the large rubber intake boot sitting on top of the manifold. You see it in the third photo. This one got torn during removal. They are reasonably cheap and easy to replace once the fuel lines and wiring is disconnected.