Wayne, I have absolutely no idea but will throw out these ideas/thoughts for your consideration...anyone with a Cub/Mod could take a set of calipers and come up with the thickness...the type of Al may be close to impossible to come up with since the Cub/Mod were built so long ago and the companies have been outta business for many years...many of the early TD were built using mil surplus stuff left over from WWII and used whatever may have been available on the surplus market...nowadaze, most builder use .032 to .060 for AL skins...the .032 is about the thinnest sheet that can easily be worked with due to the "flimsies"...the .060 is about the thickest that can be worked with without it being "too" thick to work around bends easily......
madjack
p.s. here is a link to a Cub/Mod discussion group...may be worth contacting for more info...........MJ
http://autos.groups.yahoo.com/group/mod ... teardrops/