Went with the estoril pipe and ditched the boss. Also did some base spacing with 3 base gaskets from treats so the piston will clear the exhaust port & transfers. Also opened up/widened the exhaust port just a bit (like 2mm or so) and geared out to 18/42. Using a 15mm bing carb with matching 15mm Grandpas intake with 78 jet, needle on leanest setting with metal mesh hi-flow filter (edited)