Dell,
If I'm seeing correctly, you have her back to 25" on the tiller. If that is so then that little (55") bugger is shooting damned fine. Also from what I can see in the pics (no set, and nice even circular tiller) it would probably go back another inch....but why? You made a very fine example of the type so why not live with it's limits on this guy? I believe that the original was estimated to be about 66 to 68 inches long.....you already know that at that size you could get your usual 30-32 inch draw length.
I'm sorry...I'm just trying to preserve a very fine bow....it's yours so carry on sir....and yes they are fine shooting weapons.
rich