Did you just "Unplug them" and remove the hardware ? Did you just "CAP" the "port" on the throttle body ?
You can remove everything and just plug the vacuum port on the throttle body if you don't need it for anything else.
However, without the EVAP system in place, how are you going to deal with gasoline vapors coming from the gas tank? They'll need to be allowed to vent to the atmosphere so pressure can't build in the tank. And these vapors can get annoying - especially if you park your car in an enclosed area like a garage.
If you wish to have a working EVAP system, all you need is the stock Fiero charcoal canister and the EVAP purge solenoid from the 3800. That's it. The diagram below shows how to hook it up to the 3800:
The charcoal canister can be relocated out of the engine compartment (I mount them just ahead of right wheel well cover, below the stock battery location outside of the engine compartment) and the EVAP purge solenoid can also be mounted there too. All you'll need to do is run the vent line to the canister (as shown above) from the tank and then run the vacuum lines from the canister to the purge valve and then on to the engine from there.
The solenoid/valve I have,(Doesn't look like the one "pictured"), ( Delco part #5236 2 , large 210) has both hose nipples on the Same End, the other solenoid /switch that was "in line "with it,( Fasco #24506192) has 3 hose nipples on it. I Use the one with only 2, right? Which vacuum Hose goes on What nipple? Thanks, could never do it without your help !
Yes, you should be able to use the one with two. It is probably from the 3800N/A motor, I can snap a picture of mine if needed. There is lettering on one of the lines that says CAN and it goes to the CANister. The unmarked one goes to the vacuum source either on top/side of the supercharger or throttle body (not under the supercharger snout).