Try this https://en.wikipedia.org/wiki/Band-stop_filter that can filter out the 60hz hum
Sweet build, would like to see the back side too.
Ok, here is the back side and a shot of the tuners and the 1/4" jack. You will notice that I made a change to the turnaround where the strings change direction to get to the tuners. I previously used part of a bar from an old computer printer but found that the strings did not flow freely through the holeswhen adjusting tuning. I changed it to a handle for a tattoo gun which is round and has 4 grooves to guide the strings.