20+ muncie trans what #'s should i look for

[indyjps]

i got to talking with a guy recently and he has "over 20 muncies" and about the same # of t-10's and a pile of saginaws, he used to build racing 4 speeds. i am going to check out his stash what casting #'s and dates should i be looking for, what are they worth. he basically stated he has had them sitting around for years and wants to get rid of some of them. thank for any help.