Thanks for your enthusiastic note. And, yes, we were thinking our John R. Allison, though born 100 years later, might be related to that John Allison. Thanks for suggesting the Greencastle library. Bonnie Shockley of the Antrim-Allison museum did a little research for us and we are still searching for John R's parents.
I will send you link to our Allison family tree if you would like to see what we have turned up about him so far.