Needs fuel tank pressure sensor assembly on 2001 Ford Mustang

the check engine light came on and the code is P0456, evap leak. replace the fuel filler neck grommett?? what should this cost to repair. The tech said the fuel tank needs to be replaced??

Asked by for the 2001 Ford Mustang
replaced tons of these seals common failure. seal is about 20 and the labor is about 1.5 hours