i thought it was drilled in the bottom...sry bill. Just use a tee with the cap like the other style but let the "bottom" of the tee be the "drain". the top of the tee with cap to vent and control flow rate via the drilled hole in it. and the third port of the tee put a stub of pipe into it to go to your bulkhead. Use whatever size pipe your bulkhead is sized for.