Ah, good question Stereodude. I didn't think about that.
Randy, that's a little tricker. I would try by putting the speaker in the middle of the room and place it on the floor. Get the driver and port close to the floor. What size of driver? And how far away is the port? I'd then put the mic about 12 to 18" midway between the woofer and the port and lay the mic on the floor. Sweep. See how that looks. That will have captured the driver and port all in one. If the room influences the response, then raise the speaker up off the floor, put the mic 1" away from the center of the woofer. Sweep. Then right at the port. Sweep. Then hopefully your software will have a "match" and "stitch" function. Maybe do both ways, even if the further mic position works. That way you'll see the two separate outputs. Kind of depends what you're trying to do.