I just completed a panel. Was going to offer it for sale but decided to use it on my own machine. The way i do the ventilation/cooling is filter on side bottom and fan on side top opposite side. Been doing it this way in control panels for many years...no issues. Separation between "noisy" and low voltage devices and wiring is also very important, that way noise related issues would be greatly eliminated :)
As you can see i used plugs for all the external devices cause this was a plug and play unit for sale. Same as you i used the AXBB-E and although it works good the way they designed it makes wiring a bit complicated....i am currently working on a better solution for that. Another thing i am working on is to make wiring to the sensor plugs easier and faster. Just thought this might give you some ideas for your next one :)

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