a while ago i had my head gaskets replaced and while my mechanic was putting everything back together i asked if he could put on some chromes valve covers, so he got some edelbrock covers for a good price and put them on. of course the car ran better b/c it wasn't overheating anymore but i have noticed it idles a little rougher, then i noticed he bypassed the pcv system i guess b/c of the new valve covers. now their is a filter and oil fill cap on top of the driver side valve cover and nothing on the other side. can i replace the oil fill cap with a pcv to route it back in and keep the filter where its at or am i going to have to put a hole in the passenger side valve cover to put the filter?

 

you can just remove the air breather component on the valve cover and replace it a proper sized gromet and pcv valve and hook it up to a proper vaccum source. Check your vac lines while you are at it...maybe he left one out?

 

i don't need to put a breather going in anywhere(i only ask b/c in the haynes manual it shows a diagram w/ a breather/inlet on the opposite valve cover as the pcv valve)?

 

Ideally it would be preferable to have a vent on the opposing side to properly vent. But I still don't think that would be causing your sudden rough idle.

 

You should do a compression check. If you over heated your engine you could have weakened your rings on one or more cylinders and have a loss in compression.

 

Would have little effect because you have nowhere for air to enter the crankcase to purge the fumes out.

Is not called Positive Crankcase Ventilation for nothing
Outside airflow through the engine removes fumes and passes them through the PCV valve to be burnt in engine

 

With those covers you'll have to either put a hole in the one for a PCV valve, or you'll have to live with the breather that coats your shiny chrome cover in oily residue.

The PCV valve provides a fairly significant portion of the idle air flow, so not too much surprise it idles differently after your "upgrade".