It would be best to download a copy of NHRA Rules read for yourself and send questions to your division tech director.
https://www.nhraracer.com/content/ge...000&zoneid=132
Replacing fuel lines with steel braided is encouraged. No mention of size.
There is no mention of requiring the stock fuel rail.
Can adapt the stock rail to braided lines.
Can install larger injectors there cannot be any machining of the lower plenum for fit replacement fuel rail would need to be a stock replacement.
Can install larger fuel pump and regulator must be controlled by ignition switch.
Can install fuel cell stock tank must be removed.