Been a while since I had some news, been a bit slow on my end.
But finally got the components in for the main board and got the first one built, yaaah
Good news is its powering up and accepting code uploads.
Now the fun can start getting them Mainboard and Gauges talking to each other and working with SH3.
(will redesign this one as I choose very small components - so small it was a nightmare to get them soldered. Next revision will use slightly larger footprints).
Some of the resistors are 0402 footprints, will go with 0603 for next version. Less hair pulling applying solder and getting components sitting correctly.