I'm back after a 5 year hiatus as a Benz owner and I'm pleased to see that the ShopForum is still going as strong as ever. I did do searches before and after my recent acquisition that has brought me back to the forum, but could not find exactly what I am looking for.

Here's the car: http://www.flickr.com/photos/61049394@N00/4028374138/

a 1973 280 (w114) gasoline. It has the flat top inline 6 cylinder with the plugs down the middle.

I bought it knowing the transmission flared because 1.) the tranny was way overfilled with fluid (I pumped a quart out to get it to the top fill line) and having read numerous posts, I was cautiously optimistic that it would be a vacuum leak or other maladjustment that could be rectified. Plus it only has 87,500 miles on it.

So it shifts early, and flares between 2-3. It also does not shift into 4th. The local independent Mercedes mechanic (everyone in Lansing, MI will know who that is) has not examined the car but looked it up and said that he thought the 280 only came with a 3 speed in 1973. So that may solve that.

My questions:
1. Where can I find the transmission type? 722.102 and 722.202 are listed as possible transmissions and I can’t find a chart for it. Once I’ve identified the type, will it signify whether it is a 3 speed or 4 speed?
2. Where is the vacuum modulator? Does it even have one? From the articles I’ve read (including Steve Brotherton’s article on vacuum control), I don’t draw the conclusion that ALL Benzes have the vacuum control of the transmission. The threads that I find are usually in the Diesel discussion and that is what I had before.
3. Is there a book or manual out there that I can get that will have info about the 114? I looked at the info at MZF-Bayer Transmissions and they seem much simpler than my setup. I also don’t recognize some of the parts from the diagram. The MBUSA manual specifically excludes transmission rebuilds. A rebuild is beyond my skillset, but perhaps it contains all the necessary information short of that. Any advice here would be great.
4. Can anyone tell me what I am looking at in the following pictures? Descriptions are under the photo on Flickr.

1.
http://www.flickr.com/photos/61049394@N00/4027505397/

2. There is a wire going into that grey mass. But no vacuum line.
http://www.flickr.com/photos/61049394@N00/4028257706/

3. There is a little silver valve with a vacuum line going to it behind the bar there, but I can’t figure any way of adjusting it.
http://www.flickr.com/photos/61049394@N00/4028258926