Since it seems to me that nobody on any of the Goldwing boards has ever mounted aftermarket speakers and an amplifier in their GL1800, I thought I would provide those of you that are interested, a few pictures and commentary of my installation. I'm posting this to all boards that I subscribe to, as I've had comments from people wanting to know how I have progressed. Please disregard if you have already read this...

Here are the model numbers, and the web site where I ordered my system. I found this combination to be reasonably priced for what I wanted.

Pioneer model GM-X364 (4) channel amplifier - 60W x 4
4 JVC (4") two-way speakers - model number CS-V422

Web site: http://www.sounddomain.com

All four speakers including the amp was a little over $200. Don't bother ordering an amp install kit. They are a joke! About the only thing I found useful was the (10) guage power wire, the (10) gauge ground wire, and the inline fuse holder. The (16) gauge "monster" speaker wire was useless because it was too thick and was not coded negative and positve. Instead, I bought 100 ft. of (18) gauge speaker wire from WalMart for about $8.00, which according to some experts I talked with, is more than ample for this sound system. You can pick up (10) gauge power and ground cable from any audio shop for about a $1 a foot. You could probably get a 30 amp inline fuse holder also from an audio store or WalMart. The amp instructions will tell you exactly what is required for proper installation.

(picture of the front panel) so you can get a general idea of how I routed the left speaker wiring under the dash over to merge with the right side speaker wiring. I wired directly from each of the stock speaker wires back to the amp in the trunk, and then from the amp back to the front speaker boxes. Following is how I routed the wires so as to be concealed and not interfere with anything else on the bike.
http://www.azbest.com/goldwing/frontpanel.jpg

(picture of the left speaker) I installed 4" JVC speakers all the way around. They are rated at 50 watts RMS, which make them a perfect match for the amplifier. You will have to cut slots in the speaker frame where they screw into the speaker box, as the holes are about 1/4 off all the way around and do not line with the stock screw holes. Notice the fender washers with rubber bottoms, this greatly reduces the vibration and secures the speaker frame to the speaker box . I also put mounting tape around the circumference of the speaker enclosure to further reduce any vibration and to provide a cushier mounting base. DON'T FORGET TO MARK YOUR SPEAKER WIRES when you start routing them through the bike or you will be in for a mess.
http://www.azbest.com/goldwing/leftspeaker.jpg

(picture of the right speaker) Notice how I merged the left speaker wire with the right speaker wire and started my run down one of the fairing spars. This route does not interfere with anything.
http://www.azbest.com/goldwing/rightspeaker.jpg

(picture of how I routed all 4 speaker wires along the right side of the bike) I did this so as to avoid any electrical interference from the alternator, plus there just isn't enought room on the left side with the main wiring harness and all. Here you see how I came off of the fairing spar down to the cruise control module/airbox and around the front right mounting of the gas tank. I did this to leave enough slack in the speaker wire in case I ever had to remove the gas tank as you will see why in the next photo. As you can see in this picture I used mounting tape on the very front of the gas tank to secure the speaker wire.
http://www.azbest.com/goldwing/speakerwirefront.jpg

In this picture you can see how I ran the speaker wire along the gas tank and back to the rear frame. There was no other way to do this, as things are very tight in the lower frame area to be running this many wires. Besides if the bike ever had to be completely torn down, I left it so that the speaker wire can easily be removed without too much trouble. Again I used mounting tape to secure the wires to the gas tank. Before mounting I prepped the area with rubbing alcohol. The mounting tape holding the speaker wire is very secure and will be a bitch to unstick if I ever have to remove the tank.
http://www.azbest.com/goldwing/wiresideview.jpg

In this picture you can see how I ran the wire from the side of the tank and along the inside of the frame. Again, if the tank ever had to be removed it's very easy to just cut the ties from the frame, and then pull the speaker wire and mounting tape from the tank and just drape it over the side of the bike. That's why it is real important to leave some slack in the wiring where ever there is a space to stash a few extra inches of wire in.
http://www.azbest.com/goldwing/wireinsideframe.jpg

In this picture you can see where everything comes together before being routed inside the trunk. Here you see all (4) speaker wires from the front, the rear speaker wires (purple) that connect from the honda connector under the seat, the red power wire, the blue accessory wire from the fuse box, and the ground. Notice where I made my ground on the rear frame where the rear trunk attatches to the frame. This was as good as spot as any, as the frame is the main grounding point for the entire electrical system anyway.
http://www.azbest.com/goldwing/wirerearframe.jpg

In this picture you can see where I ran the power and accessory wire from the battery and the fuse box along the inside of the rear left frame and around to rest of the wiring where it enters the trunk.
http://www.azbest.com/goldwing/powerwire.jpg

In this picture you can see an overview of how all the wiring is routed to meet at the rear of the bike where it enters the trunk.
http://www.azbest.com/goldwing/rearframeview.jpg

In this picture you can see the amplifier and how all of the wiring hooks into it. I just have it laying in my trunk for now, but this weekend I will build a mounting base out of ABS. The amp will be velcro mounted to the trunk floor, and will be up about 2" to allow for air circulation. I may even figure out a way to mount some fans to help cool the amp, as it gets very warm.
http://www.azbest.com/goldwing/ampintrunk.jpg

I hope this is of help to any you that have pondered on how to mount an amp and speakers. Needless to say... THIS SYSTEM ROCKS!

Gary Mellott
Glendale, AZ