spark plug?

Anybody know of a plug that is a 5/8 versus 13/16 plug to fit old style chevy small block heads?

 

They are just standard plugs go to the autoparts and give them a year for the heads.

 

When I bought my 327, it had tapered seat 5/8 plugs in the old powerpack heads and worked fine. I did replace them with washered 13/16 plugs when I removed the HEI that came in it.

Blue

 

Peanut plugs?

 

Thanks guys. I'll look in to it this week