Sorry for the late addition, I thought this route would be listed, but apparently it's not.
If you are coming from NY/NE on I 81 and want to go directly to the fairgounds to register on Friday, get off at exit 61, route 944/Wertzville Road. Follow 944 west until you reach route 34/Spring Road, then turn left. This will lead you directly to Gate 3 and the registration office.
The last leg on 34/Spring Road is also part of the alternate route to gate 3 from the hotel or I81/exit 52. Getting off at 944 may add a few miles (but not many) but it's a 2 lane blacktop with almost no traffic. By 4PM both Carlisle Pike and I 81 start getting commuter traffic.
If this isn't clear go to the directions page and click the scrollable map link below the hotel address.