Really? Refresh a motor with ONLY 200 hours? That thing is barely broken in yet! Heck our comp has easily 1800+ hours. And the motor still runs just fine. The Martinique had 650 hours, ran a little rough, new plugs, correct timing, replace exhaust hose, and carb rebuild its back to running perfectly smooth. Now has 900 hours just fine. I would NOT touch a thing on that motor. Except oil change BEFORE you run it!
I mean think about it. The 351W is a basic highly reliable well built low HP high torque small block V8 meant to last. Thats why they used it for so long. Our 2007 Suburban has 135,000 miles and 3,600 + hours. Only thing wrong is stupid AFM lifters starting to go. Other than that it runs great.
Change the oil, spray oil in every cylinder, let it soak, and dump 30:1 2-stroke down each barrel of the carb and if you can fill the carb bowls with the 2 stroke as well. This really helps the valve seats and stems seal up nicely. Oh, and disconnect the spark and crank it for at least 5 seconds to get the oil system primed. It takes 5 extra seconds to ensure nothing will run dry, remember, its a flat tappet motor...