Self Contained Speaker Box

i ordered some stereo stuff online to put in my girls car, but when they sent it they sent out a double order!  2 of everything for the price of 1!!
so now im gonna build a self contained speakerbox like they do with lowrider trikes, but im just gonna use mine in the shop & at bbq's.

i figure ill run a motorcycle battery for portable, but how can i convert wall power to 12v?  or should i just use a tricklecharger when im not listening?
also got a couple of questions:
do you hook the deck straight to the battery with a fuse inbetween?  what about the constant supply?
do you just use the battery negative for ground, as there is no chassis?

im gonna run 2 8's off the amp & 2 4's off the deck.  maybe tweets

anybody built one of these?  got pics?

I have built a party cooler back in the day....I used all Marine equipment and made a section all to the stereo in the bottom of the cooler so that I could still have a functioning cooler....

I used the charging unit off of one of those little hotwheels Kids toys (the little things you ride...) I used two lawnmower Batts....and had an isolator between them....

Yes I fused the the HU to the batts and didnt worry about the Acc and Const...I just wired them together and put a kill switch inline with the HU....

And yes just take the Ground straight back to the Batt....

I finally wound up rigging a secondary power input to come off of a cigarette lighter plug....

Paint and stickers and I had a Party Cooler.... Great when we were at the creek....I wound up building two or three of the darn things for friends....

Goodluck with your project...