Fuel Sensor Choice

Thank you Dave. I'm sure you're getting tired of all my questions, but just one last one
I have seen other types of sensors than the arm float types. I just need your advice because I'm afraid that the float might get damaged from the fuel nozzle as the tank is being filled as the level of the fuel rises in the tank and the float with the level. So I'm thinking that it might be a possibility of damaging the arm or the float. What do you think? 
The 2 alternative types are  a) no moving parts sensor,   b) a  vertical tube with the float around the tube and the travel is the just up and down with fuel level. If either of these two would be chosen, then I think that a 250mm long would be a good length into my tank.
Hi Atli
The Flu I am fed up of Questions - never.
The swinging arm type work fine but they do tend to swing too much on a boat. However you are limited to choosing a sensor that fits into the ohms profile of your gauge. So its best to choose the sensor that is matched to your gauge - and - a gauge that has the correct type of sensor for the tank position.
VDO gauges have a vertical sensor that needs to be fitted vertical.
The fuel level sensor needs to be fitted as far away from the fuel entry point as possible and if at all possible should have an internal baffle to stop damage from filling and fuel swilling about ( the larger the tank the more important this is - you should be OK).
The retro range are swinging arm so can be fitted vertical or horizontal.
VDO and KUS are vertical only.
Retro and VDO are bolt down with rubber gasket fitting, KUS are mostly one and a half inch BSP screw fitting.