If you are using the "Best" gasket kit, I would toss the pushrod cover gasket if it is of the black hard felt looking type... it doesn't seal worth a darn.

I never really liked silicone because of the scary places that I have found it in engines, but the red or copper silicone is great to seal the pushrod cover when used all by itself (no gasket). No more seeps!

~ Dave
1950 Chevrolet 3600 3/4-ton with 261 engine & T5 Transmission