69InBoxes,
You could try Stevens Automotive in Beloit, Wisconsin. They run a used Corvette parts business and have a lot of parts cars. The owner is Jim Stevens and the telephone number is 608-365-7116. They've treated me very good when I needed used parts.
Recently there was someone in Blue Mounds, Wisconsin who had a bunch of Corvette frames for sale on Ebay at cheap prices. I don't remember the e-mail address but Blue Mounds is a small town fairly close to Madison and if you call the Chamber of Commerce or perhaps any gas station they'd probably be able to give you a telephone number. From their Ebay listing it looked like they had a whole salvage yard full of Corvette frames and body sections.
Good Luck,
Eugene