Winfried: smallest cog = most chain wrap; tensioner arm swings up. Minimum clearance happens somewhere around the middle of the gear range, when the tensioner arm is near vertical.
On my bike with the Acolyte Supershort, clearance with chain on smallest cogs is 130mm.

Bobcat: Winfried mentioned that shifter is M315, & Maddog states that M310 RD works brilliantly with that.