Working on our master bath remodel so progress is slow... but I did build the reverse camera trigger circuit last night.
Edit: BTW, would anyone be interested in these? Ordered parts from DigiKey and Amazon so of course everything comes is 10's. Have enough parts to make up some more. Would be $30 shipped to you. These are super simple to make, I have provided the diagram for those inclined, but if anyone didn't want to take the time/effort... like I said, I have the parts.