That's a reasonable question, and it deserves a fair answer for what I would, and would not, be able to do.
For those who don't know me, my name is Matt Cramer. I have a degree in mechanical engineering and worked at DIYAutoTune for close to 15 years, where I did a lot of electrical work. Some of my experience there includes designing the DIYPNP and the original run of MSPNP Gen 2 units, working as project manager for the first generation MS3Pro, and designing drop on engine and transmission wiring harnesses.
The plan here would initially be to get a line of professionally made PCBs (no toner transfer and ferric chloride) run with through hole parts that I can assemble by hand, then if that establishes the demand is there, have a contract manufacturer make a larger run with surface mount parts.
One limitation that I haven't found a good way to get around is making stamped metal parts in short runs, which is limiting me to either finding an off the shelf enclosure (generally plastic or cast aluminum) that can be easily customized, or trying to recondition used ones (which would be a lot more involved). So I'm checking to see how much of a deal breaker this could be, and if it's a problem, I'd rather find out before I've ordered a bunch of parts. :)
Case grounds versus wire grounds have a few trade offs. A wire is another failure point, true. But I've seen reports of internal grounds to the case fail. And a correctly executed case ground still has to deal with voltage drops and electrical noise in a chassis ground - you'd think that much sheet metal would give a clean signal, but noise, spot welds, and a number of other factors interfere.
