I have been lurking in the back ground learning what I can and now starting work on a 1957 century with a interceptor marine 312 y block the interceptor model number is 215 the ser num is 35596 on the rear of the block of the rh bank just under the head is stamped 312 35556 & on the left side of the block over the oil filter the block num ECZ - 8015 - C. The marks beside the disturbutor port shows to be a Cleveland. The number on the heads are ED - ECZ-C with a 1.78 valve, this is were I get confused from what I read the heads are from a 1956 truck 272 cu.in. To my knowledge this is the original and has not been altered, although it appears that one of the heads have been taken off at sometime.

Preserving the old can be more rewarding than buying the new...