I may take you up on that plunger if I can't sort something out.
So looking 3-ways, you think something along these lines would work?
"NITRA solenoid valve, 3-port (3-way), 2-position, N.C., single solenoid spring return, (1) 1/8in female NPT inlet(s), (1) 1/8in female NPT outlet(s), (1) 1/8in...