OK...I finally have all my stuff in. I got a pair of 14 gallons and went with wheels, butterfly valves and the racking arm from morebeer.
Attached is a picture that shows how I solved my "crowded" problem.
Since I'm on wheels, I can easily move the fermenter around and get to the dump valve or racking arm. I'm going to try it out that way. Having them both point forward was very tight.
I have the butterfly valve at an angle away from horizontal. If I have the handle horizontal....I can't close the valve unless I rotate the 90 elbow away from perpendicular to the legs (or do what I did). Again...tight fit. The pull handle version of the butterfly valve may be shorter (worth a look).
I also played with having the butterfly valve mounted pointing straight down (losing the 90 elbow), but that seems like it would make the bottom of the valve very hard to clean. I may try this at a later date.
I had a little problem with one of the racking arms. One of the arms fit perfectly in both of my conicals. The other bumped into the cone of both of them. I ended up having to trim about half an inch off of the arm. I didn't get too much into looking at lengths or angles, but I imagine it was some combination of the two.
The other trick I did was....I got some extra STC probes off of digikey and "permanently" mounted one in each of my thermowells. They fit in the thermowell with the SSbrewtech thermometer at the same time.
I terminated the STC probe with a RJ45 and mounted a RJ45 coupler to one of the legs of each fermenter. So...as I move fermenters in and out of their respective cooling chambers, I don't have anything to do but plug one RJ45 in.