I just finished installing a new head and I come to find out that the plugs that I bought for it are too small and it looks like it uses a flat instead of tapered seat. The heads casting number is #3895052 and is used for about everything from 1967-1990. What do I use? This is going in a mildly modified 292 with HEI in a 1978 Chevy C-10
Thanks for any help, Perry
