Great buy Walt, you got a DEAL! Did the shop owner have any idea what happened to the frame? Did he have any more 'parts kits" at that price? <img border="0" title="" alt="[Eek!]" src="eek.gif" />
and YES, it may require some minor fitting or lapping to make sure that the function is smooth, but you are correct that you should be able to put either the .30 caliber or 9mm upper on your frame... I would replace the mainspring with the one for the 9mm... there is an article on how to do this by THOR in the Technical Information pages.
Headspace could possibly be an issue, but I doubt it...it is not very likely...
