Rebuilding my 470 2 barrel.I picked up a 4 barrel intake manifold for it. Need to know the Rochester model number. Would also like opinions on other carbs vs the stock carb, [like a Holly].Also are the cfm ratings the same for the 470 - would a 650 vs 750 make any difference ? Is there anything else needed to go from 2 barrel to 4 besides gaskets ? Any other input on bumping her up to 188 hp is welcome,thxs.