Now that the tank is up and running I thought it would be a good idea to at least update this thread. Overflow is working perfectly. The height has been perfect as well. For better or worse I eased my access to the back fears by placing the tank and stand a little over 12" off the wall in the office. There's enough room for me to squeeze back there, at my current weight at least, and get access to everything at the expense of making my office seem smaller than it already is. Function over form in this case. I'm still playing with stand pipe heights in the back box. Sometimes the full siphon starts quickly and sometimes it never does. Easy to get it going if it needs a little help though.
Also, in place of teflon tape I used a teflon paste instead. After doing some reading it seemed the more prudent choice for a permanent seal of those lower holes and they've been perfect after a few months of water in the tank.
