I've always felt that the battle of Medina would be somewhere between Pleasanton and San Antonio, with the actual site being somewhat closer to San Antonio....looks like you are in the right area ole buddy.
I wish you luck in your quest! Maybe one of these days we'll be reading about Mike from Treasure Net that solved the mystery of the Battle Of Medina!
I would love to see some pictures. I was going to head to the "Medina Hunt" last weekend just to see what there was there but I believe that it is further South just by doing some light research and talking with my buddy in SA.
There is some land that needs to be checked before it becomes development soon.