110 should be fine, and yes, degree the cam in at the cam card specs and be sure to check piston to valve clearance, rod to cam clearance and rod to block clearance. Rocker ratio may depend on the cam choice. I ran a Comp 12-609-5 in a 13.5:1 406 for years and it made great torque. I had 1.6's on the intake and 1.5's on the exhaust. The 383 I told you about has a Comp 12-612-5 in it with 1.6's on both but he's lighter than you by several hundred pounds. I'd go with the smaller cam or something similar if it was mine. No, you don't need to rock the block. 1 3/4 tube is best, but no bigger than 1 7/8. Bigger tubes kill torque.