My buddy has a Gem car that he was comletely redoing so he had my friend and I do the stereo for him. It was a fun project that I thought you guys might enjoy. He gave us all of two days to bang it out so its not totally up to standards but its pretty damn cool as it sits.
In the front console we did a pair of Polk Db651's, a Clarion EQS746, a color matched power switch an iSimple IS76 periphial for iPod power and signal.
In the back we did another set of Polk DB651's, a Polk DB10 in a sealed enclosure. We would loved to have had more time to do a proper enclosure but this will get him by for now. The whole cart frame is aluminum so we cut out an aluminum plate and fit it between to of the uprights and mounted the Kicker ZX550.3 on it. It was a super tight fit once the wires and cabling were ran to it.
The batteries were another challenge. We had to build some brackets out of steel and fasten them to the underside of the frame where some open areas were. He had bought a couple Exide group 27's (wouldn't have been my choice but whatever.) We also put in a Schumacher charger that we converted to an onboard. We rewired it and put in a remote charging plug and while we were at it we moved the charger plug for the cart batteries as well. I put the fuse up there as well which is good and bad. It's right at the batteries but if it pops its a bitch to get at.
It was a really fun project I just wish we had more time to do a better job in a couple areas. We are gonna redo the box covered in black vinyl and put in a couple cup holders as well as do some neons and LED's.