Ford F-150 - 1997-2003 :: Loud Knocking At The Passenger Side Valve Cover - Camshaft Not Getting Oil

I have a 98 F-150 which has a loud knocking at the passenger side valve cover. I am not a mechanic but thought it was a rocker arm knocking. I dropped some oil from the oil pan and did not see and metal shavings. I added some mystery oil but the knocking continued.Loaded the truck on a trailer and hauled to a mechanic to check for the problem. He said the oil ports are clogged and oil can not get to the cam shaft and the cam shaft bearings are probably causing the knocking. He said there is no way to fix this problem and I will have to replace the motor.

I called another mechanic and described what the other mechanic described. The 2nd mechanic said it would require a complete tear down of the motor and would be cheaper to replace the motor. I recently bought this truck just to use for hunting and around town since it already has 198k miles on it.

Is there any way to clean the gunk from the oil ports? The truck will still run but just has the loud knocking so I don't let it run for more that a couple minutes. I have been reading many opinions for sludge blocking the oil passages and am considering removing the valve cover gasket and filling with diesel and let sit for 24 hours then repeat then put in fresh oil and filter. Maybe this will clean the blocked passages.