The affordable DIY systems work OK on virgin concrete, and then only if all you do is drive the car on it and park. Once you start really WORKING with the floor and drag jackstands and floor jacks across it, all bets are off.
------------------------
Mike Burch
66 mustang real street
302 4-speed 289 heads
10.63 @ 129.3
http://www.mustangworks.com/cgi-bin/moi-display.cgi?220
