Survey; Which relay to power fuel pump.

[Accelo]

I have a choice of two relays to power fuel pump. Both are already installed.
One is part of the American auto wire harness.
The other is included as part of the computer, ecm, conversion LSX motor install. My fuel tank has been relocated to the rear.

The difference may be how they are switched:

The conversion auto wire system has a relay that comes on with the key. And stays on till you turn it off with the key. This relay is located on the left side and is powered through the firewall plug.

The computer, ecm, conversion harness for the LSX motor has the pump relay coming on for three seconds and then shutting off unless it sees the ignition signal. This relay is on the Right side next to the battery.

Pro & Cons;
The conversion auto wire set up as it has the fuel pump wiring included in the tail light bundle for a clean install.
The computer (ECU) conversion relay is on the wrong side for ease of wiring. I would have to run a new wire down the right side frame rail. However, this may be the safer of the two as the pump isn't running without the motor for longer than three seconds.

Question is which wiring scenario would you choose?