Yes- I could actually see where it would be useful to be able to work into the circuit from both ends with the probe in order better drill down on the problem area.
Just to clarify, I was never getting sound from IC1, I just wasn’t communicating clearly what was happening. I think the chip was bad from the get go.
To conclude the story, tonight I stared at the area around the input for about 10 minutes and realized I had reversed the hot and ground wires when I soldered them into the board, which certainly explains the readings I was getting. I reversed them and the pedal is now working!
I am most grateful for all the help and patience you provided! Building pedals for me has always been about just following directions carefully. I understood how the off board wiring all worked, but had no idea exactly what happened when the signal reached the board. This has been a great introduction toward beginning to understand circuits, and now I’m excited to dive in further. Here’s the final build: