Piston Blow-by

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1989 Ford F-150 SuperCab, 302 V8, 5-speed, 235,000 miles.
did not see a topic for Blow-By which is what I believe my engines problem is. The engine uses about 1 quart every 100 miles or so. No smoke out the exhaust. Engine breather is soaked with oil and intake parts are coated in black stuff. Engine runs fine, maybe a little low on power. Anything beyond an overhaul that I can do to help this problem?