Valve stem seals

At what point is it a good idea to have the valve stems cut for p/c seals? The cam is only 503 lift so I doubt I will be whacking the factory style seals.

What do shops usually charge to do this?

What does a valve job usually consist of? How much can one expect to have to pay?

The valve guide boss you mean and usally its when your cam requires dual springs because the inner spring has such a small diameter and its done to also lower the height of the boss for high lift cams and i'm sure some people have done it for better oil control. i think i was quoted 80 bucks for a pair of heads before.

From what I was told when I was reworking my heads if you are going over .540 lift they needed to be cut the valve guide for clearance to keep the valve spring keeper from smashing it and as said if you use dual springs they have to be resized to fit the polylock seals they are smaller.I bought the tool from summit and did my own.It was going to cost me $350 for a valve job and have them cut not sure what the machine work would cost but I paid $75 for the valve to be ground and I did everything else.