[wingnut60]

I use a regular propane bottle and carry it in the back of the pickup--been using the same refill for over 3 years and not used it up. It has a 'Tankfoot' on it to keep it upright and it clears the pin box ok. It is kind of in the way at times, but not so much that I want to use propane out of the trailer tanks and go thru refilling them any more than absolutely necessary.
And remember, if you tie into the trailer tanks behind the regulator, you can't have a second regulator in the system on the grill...
Joe