DJRI

Second video is more helpful. Pro tip have an extendable magnet in case a rocker falls in the valve train. Its not the end of the world if it does. I advise unhooking the battery leads too.

Tighten the manifold bolts down in this order. 1 is coverd under the volume bar.

Youre looking at 500 plus for rockers. I did mine myself. Found some videos on youtube. If you do them or a mechanic does. Make sure to replace both valve cover gaskets. I did the the repair around similar mileage to yours. Hell since youre past the mileage and have to take off the pcv valve anyway. You might as well replace that too.