If a high hole gives you too much water to lug around on your kickboat you can always drill another hole a little lower. Drilling a hole a little lower is easy, but plugging a hole and drilling another higher is harder since the plug never seems to stay in long without a hassle. I've got mine set with a 10" depth so I don't have to fill my 28 Gallon box, which would weigh approximately 224#s. As I have it I'm holding around 12 gallons for about 96#s, which is still a ton of weight on a kickboat.
Tight lines,
Wade