Sorry for any delay in replying - it’s the work week again and my time for working on this has been limited. I have been reading the replies and continue to appreciate the advice!
I don’t have cardboard separating the two but I do have about a yard of electrical tape around all exposed contact points for the 120VAC except the NO/C terminals on the relay that switches it, which will be covered next. Which brings me to…
I saw that suggestion back in post #9 and have updated my design to switch the hot line, as shown in my updated block diagram in post #15.
I get how that works with a standard receptacle - are you suggesting that I replace the GFCI receptacle I have with a standard?
Thanks,
Mike