273HP intake manifold

Either the cast part number has the last 2 numbers reversed or my casting number chart is wrong. My chart shows 2536536 is for '66-'67. I would like to know if your I.M. has been altered or milled in any way. Are the mounting bolt perpendicular to the port face and what size are the bolt holes? I may also like to make an offer.
Thanks,
Either the cast part number has the last 2 numbers reversed or my casting number chart is wrong. My chart shows 2536536 is for '66-'67. I would like to know if your I.M. has been altered or milled in any way. Are the mounting bolt perpendicular to the port face and what size are the bolt holes? I may also like to make an offer.
Thanks, Richard
3/8" hole perpindicular with flange. But, notice the picture under flange around bolt holes. Doesn't appear milled or drilled to me.

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