Hey, that setup looks sort of familiar!
I drew up a concept to do something similar a couple of years ago...I haven't done it solely due to lack of $$. My setup would fit 8 gauges...six 2" and two 3 3/8". I figured on putting a speedo and a magnetic-read tach in the 3 3/8" spots, and using the others for pyro, boost, water temp, oil temp, oil pressure, and fuel level...and then putting a voltmeter and an ammeter below the cluster in single-gauge bezels where my pyro and boost currently are. I'm also thinking on the line of using a wood panel and mounting it at the very edge of the current dash layout, so it's as close to the driver as possible.
But, with all Isspro EV gauges, I'd be looking at $1000+...so it's a distant-future project...
I'm not a big fan of Autometer gauges, but otherwise looks like a very clean install!!