The block dimensions are the same on all small-blocks('55-'96) with the exception of the early 265ci, and the early Nova blocks.
How tight is it?
Does it keep you from being able to bolt up the mount?
What part of the header is hitting?
Have you contacted the seller about it?
Can you bolt it up, and maybe "persuade" the collector away from the mount boss on the block?
Welcome to C3VR, btw!
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Joel Adams
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