Question About Vibration Dampener Torque and Alternator Bolt.

I know these are novice questions but here goes. I'm installing a new vibration dampener on my 318 and the factory service manual I have says torque the bolt to 135 ft lbs. Well, the bolt is still turning and the dampener is getting very close to the timing marks on the timing cover. Is the dampener hub going to come up against a hard stop of some kind at this point and allow me to apply the correct torque? Right now it seems as though the dampener wants to keep moving aft until it hits the timing cover. How close to the cover does the dampener usually sit?

The other question is about the bolt that holds the belt tension on the alternator. The one that tightens up in the slot on the curved bracket. What size is that bolt supposed to be? A 5/16 18 bolt threads in easily by hand and seems to have the correct thread pitch, but it's a little loose in the hole as if it's too small for it. I know those bolts should tighten up solidly to hold the belt tension, but mine just seems wrong. I don't want to torque it for fear of stripping the threads out of the alternator.