1987 GMC V1500 5.7 TBI fuel tank selector valve ??

[NastyBuzzard]

Ok so I'm having problems with my truck. Have a good long forum going on on 88+ thread. I've got hesititation/stutter/misfire under load.

Took fuel pressure and got 18-19 psi on supply line while running.
Took fuel pressure for return line and got 20 psi while running.

Checked everything and it ended at selector valve (6 port). No fuel was getting past return port on the valve back into the tank.

Now I'm looking to purchase one. Found PN FSV1 (49.99)(3 port) and FSV2 (62.99)(6 port)

Even though it says 3 port it looks like The just the 6 port but with like vacuum caps on the other 3 ports. Anyone have an ideas on this???