I know where a 3406b @350 hp is setting in a 1986 maroon truck. I bought this truck in 2003. it only had 100,000 miles. I ran it 2 years,  Then a  sleeve rotted threw. When we first got it the anti freeze was very dirty.  I did a complete inframe on it then. When we tore it apart there was very little wear in the engine.  I wanted a sleeper truck and sold it to a area farmer. It was used very little.  Now I see it seating behind a repair shop. Heard the frame was broke.  If you have interest I could check it out for you. Email is in my profile.