You answered my thoughts. Prior to changing heads, etc., run 3 1000 mile oil changes with new filters and a qt. of trans fluid with each change. Open up the passages and clean out and scum before you change parts. Check with Clearwater Heads ,usually on ebay, they have good pricing and customer service. Also carry update parts/mods on their heads if available. If you check out Pennzoil or Quaker State extended mileage motor oil you will find they add friction modifiers to combat wear and are designed for old and newer style engines.