2004 sportster stereo

Hello Fellow seadoo boaters, i just picked up my first seadoo boat. 2004 seadoo sportster le and i am wanting to install a stereo. I am looking for pointers on where to install the head unit, 2 (or maybe 4) - 6 1/2 speakers and a 10 inch subwoofer. Also, i havent purchased any of the equipment...