I just bought a 1974 454 with 132,000 miles on it. Actually I bought the whole truck as a donor for installation of the engine in my 1972 4wd 3/4 ton pickup. Both trucks have auto transmissions. The engine runs but has not been used for last 3 years. Oil on the dipstick had brownish specks about the size of a pencil point. How do I tell the difference between sludge and metal specks? Most of the mileage on this truck has been around town hauling gravel and granite. What would be prudent improvements to consider for this engine? I will haul horses on the highway at about 2800 to 3100 rpm and crawl up to trail heads. Probably put 2500 miles a year on. Thanks from Coupe in Montana.