You will need to clearance a small amount off the bottom of all 8 cylinders. Easy enough with a carbide burr. There is a "stroker clearance tool" made for the Windsors. They sell them for the 351w to 408w and a 302 to 347. Its just a template you bolt to each main 1 at a time then draw the marks in the template with a sharpie, then grind all the sharpie marks off and viola a stroker clearanced block.