thanks guys - I'm really glad to get that mess of electrical wires up and out of the way. I'm felling my age trying to contort my body getting up under the stand to mount boxes wires etc., but I made some good progress getting most of it done.
Hop - I considered the removal, it's going to be hard to get a wrench on the canisters but if I have to the whole unit just slips off as it's mounted with the key type slots, a simple lift and it's off. For something I plan on only needed to do once a year I can live with the restricted access as I just didn't like my other options around my house. I cranked it up today to manually fill the top off unit and it worked great. I was a little concerned with pressure drop with the 70' of tubing but I got good flow.
here are a couple pictures:
this one shows the auto top off power and the heater power. The heaters are dual controlled (RK2 and internal). The ATO is on a switch that is also controlled by the RK2 so when in maintenance or feed mode the rocker panel is off. I have one of the rocker panels hooked up to the RK2 as a skimmer, so when in feed mode everything on this panel will be off.
I think I'll add some splash guards to those plugs - just in case.

Also the heater controllers (only one of 2=two installed) and the ATO boxes are Velcro mounted, easy to remove just in case.
This picture shows some of the wire routing up and over my closed loop pump.