Well i finally got tired of my drain line leaking on the oil pan and i changing over to a turbo header my question is im running 10an drain lines and i want to tap the block. Would a 3/8 to 10an be okay? or a1/2 to 10an? Is 1/2 to big for the dimple on the block? Also were can i find a 3/8npt or 1/2 npt tap? Thanks
