I did a fair bit of testing this morning and most of what I need the OCS to do seems to be working correctly now (software and hardware.)
Roof seems to do what it should. DC motor MOSFET works. Nice having the LED to see it kick on and regulate the power.
Direction relays work. Limit switch inputs work.
Had some bugs in the thermostat code but that seems fixed now. Buffer overflow, incomplete refactoring, etc. Sees the inside temperature and turns on the heat relay as it should.
I have a few touch-ups to do with soldering and move the onboard (inside) BME280 address so it can co-exist with the outside one. Basically it's done and ready though.
Looking good for installation this Saturday.