valve cover is easy, fuel pump is a little harder. It's easer to replace it when the valve cover is off because you can see the cam lobe and place it in the low point. Rear main = major job, front main not so bad but you need some tools. Once you have it clean park it in a spot and place some cardboard under it. Idle for 10 minutes and look for oil spots. Then trace the oil with your finger to the source.