The only issue that you have to consider when fixing the speakers is that the backplates aren't flat, so make sure that you don't apply the screws too tightly, otherwise it might cause the acrylic to break, apart from that, this step is fairly simple;
Locate the desired location for the speakers.
Make sure that all the wiring is in place correctly.
Position and screw the amp in with 4 self tapping screws.
Position and screw the speakers with 4 self tapping screws each.
That's it, now you can listen to you music with a pair of speakers that look good and work well! :D