Bike Sound System Trailer..again

yeah, i started the ball rolling on a soundsystem a few weeks ago, but i've been busy moving house the past week or so. and now i've got no internet connection in my new place so i've barely been on the forum.
maybe we could combine our efforts?
someone on the other thread offered a car amp to the cause and i've got access to loads of bits of an old soundsystem (albeit in newcastle). i've got some bass bins in mind that would be perfect and are just sitting in a mates garage at the moment.

That sounds like a plan, I potentially have a battery we could use, how big are the bass bins?
I need to measure up my trailer chassis