VS 2008 Working With Offsets

Im creating a application called FS Acars for a game called Microsoft Flight Simulator. In my acars there is a feature where you can Get the fuel load from the plane, And then you can load the fuel back on. To get the fuel from the plane, You have to use the following code;

CODE:

Ok, so once you press a button called 'Get Fuel', The amount of fuel on the plane will be shown in a Label and also be put on a Track bar, Both in a Percentage Value. Now I want the user to be able to modify the track bar, And once they have done that, They can press another button called 'Load Fuel', Which will get the value of the trackbar, And send it back to the plane to load the fuel. Can anyone tell me how I mite do this. I can allow teamview access to show an example.