Hi Momma, Welcome to the forum, lots of great advice and help is always available here.
re speakers:
I had a pair of these for 25 years on my boat, recently bought a new pair of the same to replace the old ones.
Great sound and a quality product.
I mounted mine on either side of the hardtop radio box
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re stereo:
I have an older model similar to this one: (mine does have a CD player ...which I never use BTW)
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Mounted it in the hardtop radio box.
I used to use the Sirius application but cancelled the service since what I use most is the AUX IN, to which I've connected an old iPhone that has been erased of everything except the music app. I've copied literally hundreds of my favorite CD's onto the phone, and with the music player on "shuffle" I always have what I know are GREAT tunes playing.