23 hour later it was done; the engine transplant from my wrecked 1990 300E to my 1989 300SEL.
What a job, I hope I don’t have to do that again for a while. Several stuck bolts, one busted bolt, and lots to switch over. The alternator bracket, AC compressor/PS pump bracket, bearing (fan) bracket, water return lines, motor mount brackets, and a couple of sensors had to be changed. Additionally, the throttle linkage had to be changed along with opening and closing a few vacuum connections. I left the transmission in the car and had to line up the engine to get it connected; that was a job. In hind site I think it would have saved time and effort to take it out and put it back in together. It was worth it though the engine runs like “Jack the Bear”, just perfect.
There is one vacuum connection that I am unsure about and I could use a little help. The front most sensor, a thermo vac valve, on the top of the head has two vacuum lines running to it. One line, which is on a slightly angled fitting, runs to the top most nipple on the underside of the air flow sensor. The other line on the thermo vac valve, which is a straight fitting, seems to run to an “Acorn looking” valve. The acorn valve has three ports. The line from the thermo vac sensor runs to a straight fitting on the bottom, then a 90 degree fat fitting on the top of the acorn valve runs to the bottom nipple on the air flow sensor. There is a third fat port in the center of the acorn valve that I currently have plugged, as I am not sure where it goes. The engine runs perfectly, but this is clearly incorrect, and I am uncertain of what to do. I know this is a confusing description, but if anybody has an idea for me, I’d appreciate it. I’d post a picture but I can’t seem to get it to work.
Many thanks to this forum, especially the guys that have answered some of my previous questions. This was a big job, and I couldn’t have done it without the help. DG, thanks for helping me with the rear seal; it worked great.

Thanks!