BTW...you'll probably want to confirm with Van's whether that's really a "PLUG" or if it's the modified plug/tube that they ship with their FWF kits. The one that came with my kit was a modified plug that has a little copper tube brazed to it.
The price being $6.75 suggests to me that it's the modified setup, the one you want. 'Cuz I can't see just a regular plug costing that much!