If you're interested in expanding your offerings, may I make a suggestion? The spot I have my SG mounted I really like, but I would love a more finished/refined product than what I whipped together.
Here's my location:
It's mounted using the two screws that hold the factory ashtray mount in place. I removed the ashtray, unscrewed the mount, cut two maybe 4"x1" strips of steel, drilled a hole at one end, bent them at maybe a 45 degree angle, put some 3M command strips (trimmed to fit) on the scangauge end, and attached them using the OEM screws. Then just stuck the SG on and ran the wire to the OBDII port. This location is great because it's super easy to run the cable from the gauge to the port, and it's easily viewable but not distracting.
I got the idea from this product:
1st Gen Tacoma Ashtray ScanGauge ll holder
– Paranoid Fabrications
I didn't go that route though because I didn't like the "bezel" look nor the silver color.
If you made something similar, but with a flat mounting plate instead of that bezel/hole mounting style, and included a hole for the rear attachment for the cable, it would be another great option for folks. I'd probably buy one too.