Been here long enough to know those points. I will add: Some days I've got time and energy and some I don't.
The one I got to post in sensors just needs a look that he's not about to fry everything. I helped him in PM's to find a sensor (tried to get him to make one, hehehe, learn some physics and save
and introduced the idea of optical isolation for the Arduino but I can't say I'm an expert at any of this and especially what car power may throw it.
If he can wrap this up then Arduino gets another happy supporter ready to take on new projects.
The other may have gotten back, one Jack_Aubrey. He's making a button panel and I've already suggested a much simpler way, ie multiplex pullup rows and columns that selectively ground rather than HIGH through resistor-per-button (>50 buttons) and some other bits. Well, my way the circuit drawing doesn't look as impressive....
I hope he returns.
Neither one of these guys is a forum jaggoff.