Really?? You're going to cut a 50 psi FUEL line with an abrasive (sparky!) cut off wheel? You're going to generate a lot of abrasive and sharp metal shavings around a fuel injection system that is very sensitive to debris? What's wrong with an axe?
Just take a pair of electrical side cutters and cut into the loop. Easy-peasy.
"Dad, can I get a motorcycle when I grow up?"
"Son, you can't do both"