For those interested, I seem to have figured out what the "Pop" is over the weekend. The upper strut mount on my driver's side had compressed which allowed excessive play (Wobble) in the top of the strut assembly. I was able to isolate and could reproduce the "Pop" sound with the assembly out of the car. Definitely coming from the excessive sloppiness of the bearing and additional room for the spring to wiggle around since the compressed upper mount wasn't holding down on the strut as tight as it should have been.
The taller strut mount in these photos is the new one.
Edit 8-9-19: This guess was incorrect. The popping returned shortly after installing the new upper strut mount.
The correct fix was to install a 1/2" Grade 8 Lock Washer under each of the front top strut nuts. Photo is below in this thread. There was too much slack in the strut assembly, since the H&R springs are shorter than stock. The nut was bottoming out on the shaft and the assembly wasn't quite tight enough, allowing it to wobble up and down about 1/8".
Looking at this photo, you can see that the bearing itself sits in a much higher location on the new, uncompressed mount:
