What MF and MM said.

Handiest thing I have "invented" for replacing a tank is to stick 9" Nylon cable ties in the fuel and pressure hose before fitting it into the plane. These are easy to thread through the bulkhead; even with the engine still in place.

I replace my fuel lines every Spring. Saves much of the wasted time tuning an engine only to find a small hole sucking air at the tank fitting. I can't tell you how many times mystery dead-sticks with 1/2 a tank of fuel left or irregular throttle response (falsing lean settings) were due to a pin-hole in a fuel line to the carb.