Speakers on my roll bar?

Ok, I am going over my options for my audio system. I was thinking that the stock rear speaker location is too low for optimum sound. I was looking at some older posts, and someone was going to buy some of those marine speakers that are waterproof and mount them to thier roll bar. I was thinking of that, but I don't need them to be waterproof. What if I got some 6x9s and some cheap boxes and mount them somehow to the bar? I'm thinking of (in order to keep them from blocking my rear-view) mounting them low on the bar and pointing them forward and up. I think it would bounce the sound off the ceiling pretty well. Would this work and more importantly, how would I mont them? ZIP ties?

yeah i mounted a couple 6x9 speakers to my roll bar, it works pretty well. I mounted them on the rear bar of the bottom Y section. I used U bolts on two places in the boxes. Makes it easy to move the speakers up and down the y section and swivel the speakers to face the way you need according to space if your packing the back full. Also with the top off you can move them above the bed top and swivel them to pound out if you're at the beach or in if your parked, driving. I had thought of mounting them on the bottom of the top bar but yeah you lose all your rear view.

I have been quite happy with the side mounds and the adjustability of the boxes and U bolts. Getting the angle up is a bit tough due to the bar, but i guess it depends on the angle of the boxes you get.