Chevrolet Repair: sending unit-fuel tank replacement, tank unit, fuel tank

Question
I have been told I need to replace the sending unit in my fuel tank because it was rusted to the fuel pump and couldn't be removed when they replaced the pump. Would the truck have run without the sending unit? - is the sending unit actually a part of the pump - or even attatched to it?
Thank You for your time and expertise.
Roger

Answer
Hello Roger,
I have seen the sending unit rusted in pickup tanks, but the vehicle will run without the sender...it just operates the gas guage.
The sender and pump are kinda mounted together, but the pump can usually be replaced on it.
It is often easier to replace the complete tank unit, and obviously the profit margin increases.
Van