Yes, that is the correct one. The picture I posted is from my car which is also a 1970 US spec car. Also check the "Y" pipe right under the throttle body.
If you have an interest in preserving originality or perhaps showing the car as a survivor at a Mercedes event I would be more than happy to spend a few minutes and lay out a plan of what to change and where to buy it so you don't end up having to back track and re-do things that you might be facing right now. Little things like proper hose clamps (There is a treatise on hose clamps in our tech manual) can go a long way toward tidying up under the hood.
As Jonny B said take a ton of picture now before it changes. Under, around, inside. Wherever a camera fits. There are tons of pictures of things like upper engines but very few of the lower stuff and most of the pictures I have uncovered after countless hours of digging are taken after someone "spiffed the car up" for resale.