You might wantto see
this before you pull the trigger on that amp.
Also, keep in mind that those individual speakers are specifically designed to work witnin that enclosure. Taking them out of that magic box might well leet out their magidc smoke. Also, they are 6 ohm. Keep that in mind when watching that linked video.
If anything, I'd recommend a pair of standalone automotive speakers, say a pair of 6x9's for that boombox project.