A picture of the front of the engine would help immensely; there are quite a few styles of front and rear mount plates for Chevy engines in marine applications. Look it over really well, see if you can find any numbers or markings on the mount plate; the casting number indicates the block is a '64 to '67 327 with 2 bolt main caps, and a universal application - in other words, it was used in many different applications; a generic engine block if you want to call it that. So, as I said before, any first gen or second gen small block Chevy will fit in it's place, you just need to be careful not to overpower your hull.

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