I've upgraded 15 pairs of box speakers and never had a dud. Just take the pics AND hand draw a wiring diagram of the wiring and caps. DO ONLY ONE SPEAKER AT A TIME and then test it for operation. Use silver solder, decent speaker wire and don't spend too much time soldering the wire to the drivers as you will melt the plastic anchors.
Parts quality and cost of course are variable. Solen and Panasonic worked most of the time with Auricap used in only one of my projects.
Parts quality and cost of course are variable. Solen and Panasonic worked most of the time with Auricap used in only one of my projects.