Removed the fittings from the oil filter spacer. Removed the o-ring, and drilled to 7/16 as the installation manual calls out. Tapped these for 1/4 NPT. Had an extra 1/4 NPT fitting sitting around so I used that to judge how deep to tap - since it's tapered, the more you drive the tap in, the more turns the fitting can make before it's tight. Need to order the fittings to go in here.
