The engine is the same as thousands of 350's. I would use the 305 heads in this situation. ONLY, because they will have no-lead compatible seats, where the 350 heads would cost you well over $300.00 just to get usable. I very seldom use the 305's because the port "window" is smaller and you lose top end. You will find your S-truck to be a budget tire fryer with the 305 heads. A re-ring type engine kit, HD timing set, new oil pump and a mild hydraulic cam and lifters. Budget, power and reliable. What more could you want?