Nitrous plumbing A1A...??..

I put quick disconnect crimp connectors on my solenoids.
To purge and check your fuel solenoid simply unplug the Nitrous solenoid wires. Start your car, arm your system and activate it (I just press my WOT switch) and the extra fuel will either stall or bog down the engine. Do this at idle...
As far as plumbing, what size line are you running from your bottle?
Typical small kits use a -4an (which is what your previous inquiry of the N20 PSI gauge is spec’d out for).
Larger kits use a -6an line from the bottle to solenoid.
I'm going to use the four n a as I'm not looking to shoot my eye out LOL...
I like your idea even better instead of having juice go to the fuel solenoid and having a purge button maybe just having a disconnect switch for the nitrous or leaving it unarmed and checking the fuel first and then arming the nitrous as far as turning on the bottle and stuff like that.. I've got to have an Purge kit for the nitrous I mean what's the point LOL being as it's more for show than go in a lot of cases and just for my learning and being able to be knowledgeable about the subject..