I've noticed that people seem to fit the PCB quite close to the front of the chassis. Is there a reason for that? I'm having some trouble fitting everything inside my chassis but I'd have no trouble if I could move the PCB so it's about 1.25" away from the front. There's plenty of room to do that. If I did, the middle tube would be about an inch closer to the power transformer. Does anyone know if doing this could induce hum from the transformer into that tube? That would be a disaster so I'd like to know if it's even possible before I go ahead and drill the holes. Also, would it matter if the power switch was close to one of the big orange caps? Could that create hum?