Holley Electric Fuel Pump Relay Wiring?

Dear Hive Mind -

Here is another question about adding an electric fuel pump. The idea is to wire in a relay to switched power, I currently have an MSD 6A box wired in place of the original ballast resistor and factory ignition box, am I going to cause any problems by pulling switched power to the relay that will then run the fuel pump off of the same switched power (original ignition circuit) that is hooked up to the MSD, or do I need to pull it from something else?

Any help with this is appreciated, thanks in advance.
- Steve