There is a very large parking lot with plenty of room for a semi. I would recommend going through the Cabela's entrance and use the overflow parking.
Between the outlets and Cabela's there is a large parking area that is pretty vacant most of the time.
Plenty of space on the north end of the outlets.
I did not see an area for a semi truck, but Geoff is right, you could do the Cabela's area...
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