The fuel leak at sediment bowl problem

[AriesEd68]

For my 1974 Farmall 140, I have a replacement "barrel" type of brass ferrule to try and stop the leak around the nut and fuel pipe that connects to the sediment bowl but the new ferrule does not want to go deep enough into the sediment bowl assembly for the larger nut to even screw into the threads. And the original at the end of the fuel pipe on that end was just a thing more flat round brass type washer. The new ferrule slides onto the fuel pipe so I assume it is the correct size? The smaller ferrules I have do not slide onto the fuel pipe.