My sterio in my corrado is pretty pottent. And I still have all my trunk floor space with 2 12" woffers pounding. First I upgraded my head unit to a pannasonic cd player and my front speakers to sony x-plodes. That was the easy part. The rear of the car is were the custom work begins. My stock rear deck lid was reaplaced with a cut to fit 1/2" thick ply wood covered in the same gray carpet as my interior. Next I drilled to holes in each side and inserterd metal blanks with some super glue. Thes act as the hinge near the front of the board. Then I cut two 12"holes near the outer edges and mounted up my pionere free air 12" subs. Make sure you use free air subs if you do this because box type subs wont perform right. Then in between the two subs I cut two 6"12 inch hole for my J.B.L component speakers. With my RCA cables, my power leads from the battery, my remote turn on lead and my ground already ran to the trunk I had to find a place to mount my sony 700 watt amp. I chose to put mine on the back side of my seets using high strength velcro for easy removal. Then once everything is wired up and pounding you can still enjoy a full trunk (not to mention this also looks realy cool) And since I used all inline quick connectors in a matter of 5 mins I can have the hole thing removed and the stock lid back in. The only thing different about my fabricated deck lid is that it does not lift with the hatch it is to heavy for the rubber ties. I imagine if you made your own out of a piece or rod iron or even a coat hanger that you could make it work.