vacuum leak - help
 

I have a vacuum leak on my 560SEL. I think its on the large hose that goes underneath the lambda unit. How hard is it to take the lambda unit off and then put it back on correctly? I've never done one of these, so if someone could give me step-by-step instructions, I would be eternally grateful!! If it's easier, you can e-mail me instructions at jardrewer@aol.com. Thanks for your help!! I really need to get this car running correctly!!!