I am using a old refigerator door, the old style like from the sixty works best. Sorry no pictures. They are the right size, have nice raduis, and look cool, also most of the time you can score one for free!! I you are real lucky you can get an old style that mat have a detal punched in it that will look nice on the inside of the car. This is a trick I learned from some old builders, they told me back in the sixtys they used to get all they could for all of there rides, check out the firewalls on some old rods, you will see some.
I used this crazy stuff called sheeeet meeeetaaal. Sorry not really inventive, but it's cheap and solid.
Eric, the wheelbarrow worked fine with the big block in Emilio's car, there's room to spare. Thanks for the idea, it worked great and saved some money. You'll have to come out and check it out sometime.