671 super bolt pattern help

Hi does any one have the bolt patter that a gm671 uses to bolt on to a manifold i have been making my own for a stroked 348,It start life as a four barrel 348 in a 59 chev sedan, it now as a four inch stroke, the block has been grouted to the bottom of the welch plugs, full solid roller cam, eddy heads, ross pistons, manifold made by engine builder, 671 at 10 psi.
Thanks

 

Can you use a blower manifold gasket as a template or trace the bottom of the blower? You can also look on www.blowerdriveservice.com They have the dimensions of the different size blowers detailed. Nice Engine Man! Since you filled some of the block is it going to be race only?

 

Thanks, I am putting on an engine oil coolier on, so that I may be able to drive it around as well as race.