M1 guys, intake fitting/plug questions.

Ok I bought myself an M1 MPI intake and I have a few questions about the fittings on the front of the intake. Ok from left to right there is the straight fitting that goes to the left of the thermostat. Then there is the fitting that goes into the front for the bypass. The one I can't figure the size of is the little plug to the right of the thermostat housing. This not my intake.