Someone told me you could remove something from the inside of the fuel tank (like a restrictor control unit or something) which,when removed, allows the truck to exceed speeds of 100mph, instead of shutting off fuel @ 100mph.
I have dropped the tank to replace the seal and thought that while I was at it I would remove the hinderance. Any info or help would be app.

Fuel cutoff is controlled by the PCM.
It randomly shuts off injectors when it occurs.

There is nothing in the fuel tank that effects how fast you go.