NOS Fuel Line Size

I am running an Edelbrock 50/75/100 nitrous set up on my 351W which now produces 378rwhp.
I have the Holley Blue pump feeding from 3/8" lines and 3/8" lines to the motor.
there I split through one regulator which will be set at 6-6.5 psi. My carbed motor ran fine anywhere above 6 psi in the past.
I have not yet fired it up, awaiting new pipes. I have an MSD retard which I will install. Should I run 1/2" lines from the tank thru the pump and to the motor ?
Then I figure on dropping another standard Holley regulator to the NOS. This would provide 6psi to the NOS and 6.5 to the carb BUT perhaps more volume .