ha, you just drilled a hole without taking everything apart on the inside first? I'm doing the same thing right now, drilling for these dampener adjusters on an fx in my shop but I took all the inside panels all out... your way sure looks easier

without knowing exactly where it would poke through I didn't want to take a chance... that may prove to be the most practical way to do it really once it's confirmed where it does poke through

you really should try to seal that opening as much as possible too.