LISTER TS3. Leakoff pipe??

[ROOKIE]

Hey everybody

What happen if the leakoff pipe is connected underneath the external fuel tank??

That is the case on my friend 's TS3. It looks strange to me. We have bryce injection pumps.
We plan to move the engine and, in the same time,  we would like to renew the fuel tank and piping and all the electrical wiring.

Thank you gents.

Chris.