RUN- - - -do not walk away fron that wrench jockey! He's about to get deep into your pocket with a vacuum cleaner, and ruin a nice truck in the process! His price is far too low for a quality V-8 conversion, and if he comes anywhere close to his estimate, you'll end up with a cobbled-up mess that might be impossible to straighten out. He's already admitted he has no experience with older engines, so that speaks volumes about his general knowledge.
Depending on how badly the crankshaft is damaged from the knocking rod, someone who knows his way around your engine can rebuild it properly in the $1,500.00-$3,000.00 range, parts and labor. In the event it does not need to be removed from the truck and totally reworked, a ring and rod bearing job, plus a valve regrind will be closer to the $750-$1,000 range, but don't count on that happening. By the time an engine starts knocking, it's probably beyond the point of a successful in-the-frame rebuild.
Bottom line- - - -find a competent shop with people capable of giving you an accurate estimate, and stay far away from Mr. Badwrench!
Jerry
