Will have some new info to share soon - and as a side note, a hole saw in this tough ABS is a total pain in the ass. Oh, it cuts nicely enough but the ABS disks get stuck inside the hole saw something fierce.
I wish I could laser-cut ABS, that would solve things nicely. I kind of wish I had a CNC mill - milling out the ABS faceplate is the right way to do this.