<img src="/forums/images/graemlins/notooth.gif" alt="" /> I'll add this to the timing chain issue.I recently replaced my timing chain kit with one from engbldr's kits.My old setup looked fine.No broken guides,truck ran good,but I had a rattle or clicking that I thought was the valves.So I decided I'd replace the rocker assemblies and timing chain at the same time.I was using the old crank gear to rotate the new chain to get the cam gear on.Well,that old cam gear had so much play in it that if you lifted up on it,it would spin off the key on the crank shaft.I also saw where the chain looked like it had been scraping against the block.Like you said,you don't know the history of this truck.My advice would be to not rely on how the guides look but to pull the timing cover off and check it out.Good luck! <img src="/forums/images/graemlins/cheers.gif" alt="" />