Do you have any vac problems ?
Are ther any parts, hoses, tubes, rubber elbows or other items who became brittle ? If not : don't touch them.
If you do, be sure to make a good drawing of the routing of everything. I found out there are not two the same, even not when looking at the same type of W 124. In former postings I
read that all the tubings have the same - nylon white - color now when newly ordered, not rendering problem-solving any easier !
I have made a complete plan of the tubes on my car and as it is a W 124 Diesel, it will be not of great use to you. But I see more or less "clearly" now.
Anyway, if you need help - as I have an electronic parts catalogue of the W 124 - let me know the correct type of your car
( a W 124007 ? ) and the tranny ( auto/manual) and I will take a look for you.