[Mark Yacavone]

All good ideas here.
I just like the box thing, where you can throw whatever you want in it in a pinch..Tools, chains, whatever.

I meant to post this earlier, but got side tracked.
I'm not what you call a bubblepak racer, so I build my own boxes. You don't need to be a super fabricator or welder either.
I'd just find a local steel supply in town that will sell "drops" and will shear stuff for you.
Figure out exactly what fits in your car. Lay it all out on paper, and then have your six pieces sheared. Butt each corner up and tack with your Mig on the inside of the seams. Square it up and run your beads on the inside of the box.
A couple of angle tabs facing in , with the 5/16 nuts welded underneath, and you've just about got it.
If you do it right , you won't even need to break out your H/F 5" grinder, this way.
You could be done before happy hour the same day, instead of waiting 2-3 for Buster Brown to show up ;-)