Svt Drop

Upon replacing my IMRCs with deletes, I noticed a few things. I have a 1997 Cobra.

First, one of the plugs was filled with oil. What is the best plug to use with a 100 shot of nitrous that I use once every two weeks or so?

Second, where can I get upper intake gaskets and IMRC gaskets? Both need repair.

Third, what is the best valve cover gasket to get?

Are these autozone products or must they be ordered? My car is in the shop, and i need these parts.

Thanks in advance for any help!