Hello Pinsiders! I also had the opportunity to be a beta tester. I received an 8 inch kit and installed it into an original Williams Medieval Madness. Installation did take some time, but the instructions are very clear what to do along with pictures, which I feel is very helpful. Due to the troll(s) under cabinet brackets I had to modify how to install the sub woofer speaker as the original speaker location is under the troll(s) brackets and the distance is within about 1 to 2 inches between the top of the speaker and the troll brackets. I had to remove the original wood speaker bracket, which came out not too difficulty with a strong putty knife and hammer. I had to do this because of the new sub woofer height.
Again I had to deviate from the installation instructions as I was unable to use the included wood bracket that was included in the kit due again to height restrictions. I did however use the wood bracket as a template for drilling the needed hole(s) locations. I temporally mounted it to the cabinet and drilled the needed holes.
I then mounted the screws and speaker to the cabinet. Finishing with mounting the AMP and connection wires per the instructions.
As you can see from the pictures I have posted the distance between the troll(s) bracket(s) and the new sub woofer is very close, less than an inch.
After some volume adjustments, the new speaker has three different types of controls for volume. The two on the AMP (small pots you adjust with a screw driver), the volume control on the AMP and the one on the coin door itself.
Inclusion after fine tuning to your likings this speaker ROCKS! I can defiantly say once you get it for one machine, you will want to purchase more for your others as it REALLY gives you a pinball experience a new level of playing!