float? as in the guage float? i dont think so!!!
the float is simply a device to indicate the level(not very good at it either)
the fuel pump at the gas station will still cut out at a given pressure( please feel free to read up on how pressure and volume are related, boyle's law i belive, remembered from years ago, correct me if i'm wrong). the only way to overfill a lpg tank is fill with or from something that does not have a cut out installed.
this is both dangerous and stupid, and could result in serious harm to the tank or people nearby, although i think the manufacturers are one step in front of idiots who want to get another 5 or 10 percent in thier tanks instead of getting higher capacity tanks, even on my car with a capacity of 94 litres useable, 110 rated it would only give me another 10 - 15 miles per fill!! is it worth losing the car for as there are no financial benefits to cramming more in the tanks!!
i think yr an idiot if you even try it!!!