The connection was quite easy and painless and would have been super-easy if not for my incoming WN flight waiting 35 minutes on the tarmac for our arrival gate to clear. Sitting on an idling airplane waiting for another plane to clear the arrival gate has become my #1 complaint with WN. LAS is my home airport on WN and LAS is the worst in this regard. There can be multiple free gates available, but WN is to cheap to staff them.

Anyway, at Terminal 4, I exited the baggage claim area at door 2, walked across the street, and waited about 10 minutes for the silver shuttle bus to come by to take me the short distance to Terminal 3. TSA at Terminal 3 at mid-afternoon on a Tuesday was completely open. Piece of cake, I'll book this connection again.

Thanks again for the good advice!