OK - you are at the other end of the car - under the hood.

Flare nut wrenches will help and I would depressurize the system before disconnecting the fuel lines.

Many cars have a fuel pump relay fuse or fuel pump fuse that can be removed. Once removed, you start the car and let it run until it dies.

Others more familiar with a 420SEL motor will be able to give you precise fuel line depressurizing instructions. Fuel injected cars have much higher fuel line pressure than carb-equipped models.

__________________
Mike Murrell
1991 300-SEL - Model 126
M103 - SOHC
"Fräulein"