Hi folks,
    Thanks Gary, Scott, Joel, Peder, Darrel, Sean, and Mark: My tire tray
won't be dropping onto the pavement at 40mph any more.
    I tried the lug nut first- no dice, too large. After several tries it
was the M12 hex bolt that worked best, with a fat washer and wing nut
(backwards) so you don't need a wrench to take the tire down.  Thanks again.
                                    -Matt sutton
                                    88GL