Sounds like a diy refill , probly won't get anyone to fill it for you. Might be safer to just bring the extra tank?
Let us know how you like the propane outboard! Have been wanting to get one for a while, seems like a much cleaner route for taking on the river. Been rigging my tank on my plywood floor as of late, seems preaty safe down there, guess it could freeze my feet if the valve ever busted though.
good luck on the new rig!
Think of me what you will, I got a little space to fill.