Do not put it in the FW tank. Not only is it a waste, you will not get the taste out. A friend of mine did this and all his lines froze that winter. The dealer told him it was because he put the antifreeze in the FW tank, it diluted the strength and froze his lines. It was a $4000 bill to fix!Your concern are the lines and the pump. Get a kit or make one yourself and attach it to the pump and you are set.
This spring I was cleaning out the trailer getting it ready when i noticed a hole in the hard wall through the inside wall and into the fridge door. I had it parked at my friends farm and some kids were shooting at gofers and I think one of the bullets hit the trailer. How hard is it to repair the fiberglass or could i patch it with silicone?