I enjoy playing with numbers sometimes (and I know this will drive @Captain Obvious crazy), so:
At 510 lb, the entire S30 unibody would crush down into a block of steel that measures only 12" x 12" x 12" .
(Which reminds me of the scene from the old James Bond movie, Goldfinger, where the crushed remains of an early-60's Lincoln Continental (an early American unibody) are dropped into the bed of a waiting Ford Ranchero pickup for 'disposal'. That block was probably about 3 cu.ft. but it included all of the bodywork, interior and glass too.)
The S30 unibody weighs a bit less than 5 of Grannyknot's anvils.
The S30 has plan-view measurements of about 162" L x 64" W. If the entire unibody was fabricated from 20-gauge sheet (0.036"), you'd need a single sheet measuring about 350 SF. If you wanted to make your own from 4' x 10' sheets of 20-gauge, you'd need 9 sheets. But then, allowing for scrappage from the cut patterns, you probably need to actually buy about 30 sheets. A 4' x 10' sheet of 20-gauge hot rolled steel sheet currently costs about $90, so that means your bill out the door of the metal supply shop would be about $2700. You could probably recover half of that by selling the scrap to a recycler. So let's call it $2000 for the material needed to make your own S30 unibody. Freight, taxes, and labour costs extra, of course.
If you started with a single 348-SF sheet of 20-gauge that was 64" wide (same as the length of of S30) and laid it crosswise and centred under the car, it would extend two car widths on either side of the car outline.