I hate tell tales on the spinnaker..."Sail the cloth" <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" /> (but seriously). IMHO, tell tales don't give you enough information when flying a spinnaker and are a distraction. Keep that luff curling ever 5 to 10 seconds, learn to anticipate the puffs and lulls, and everything is good. Na na na na na na .... Na na na na na na....

Definitely stainless (or monel) rivets to attach the blocks to the beam.