So I'm planning on doing this Thursday with my own spacers, and I am only doing 1/2" PVC because my RF speakers aren't very deep.
To make sure I understand... You mount the spacer in the 3 hole existing triangle, and then mount the speaker in a created 4-hole whatever set up for the speaker just in the spacer, without going through the door, right? So my speaker screws, 1/2" should be fine? Or should I go all the way through and do a longer screw? Would that just create more spots for vibration or would it make it less prone to vibrations and movement because it would be "extra secure"?