I agree with all the advice given. Check all the cheap and easy fixes first. It's unlikely that the dowels are having probs however, I just did a rebuild with a friend and one of the rocker arms with the spring loaded dowel (the last one of the three)was "jammed."

To find your oil screen:
go to the vtec assembly. It's right in front of the distr and has the vtec pressure switch and solenoid. It has three bolts holding it to the head. Be sure to have a oil rag handy. Oil will dribble out as soon as you pull the assembly off.

BTW pulling cams are easy. Putting them back on is a pain. You'll need to move the cruise control, power steering pump, and driver side engine mount to have enough room to tighten the pulley tension bolt. You'll also need two people for the timing belt. One to put tension on the belt and another to tighten the tension pulley.

hth