I wanted to have these before I knew the '12 SESG was coming with bag speakers, and "wouldnt fit". I was contemplating how/why they couldnt be installed when a friend mentioned that he had a set of aftermarket racks that I could have. So I went to work checking every spot to see why they "wouldnt fit". They do. Its a bit more work, but that is nothing new for these bikes. they install is mostly the same as regular bags, so I will just highlight what is different.
lining them up

The speaker screen has 4 t-20 torx bolts holding it in place. I found its easiest to also undo the lid retaining flap to get to the last bolt. I had to notch the front of the speaker's mounting ring to clear the bolt head.

Each bolt has a lock washer, larger metal washer, and even larger plastic washer. I didnt use the plastic washer up front for clearance, two washers will have to do. I forgot to take a picture of the hole in the screen. The first screen I tried to cut out the metal between three holes. The second screen I just bored out an existing hole and adjusted to it. this was way easier and 2mms off wont kill me. I attached the screen to the rack, laid it in place to adjust, and tightened it down. I put the screen bolts (just 3) back in before putting in the two rear bolts.
the rear bolts easily clear the Ipod module.

the front sits a little higher than average, this is due to the speaker screen's lip and mounting surface.