After running the 454 in the 78. I ran it for a few mins for the first time with the new carb. When I turn the key back the engine doesnt shut down. Then I had to pull the coil wire to hei to shut it down.
Do you have an aftermarket ignition box like an MSD? If so, then you're getting feedback thru the dash light and need to install a diode in your wiring. If not, maybe the power wire you have feeding your distributor is a constant 12v wire and not a switched 12v wire. Turn the key off and see if there's power there. If so, you ned to change the wiring.
I had the same problem when i put my 454 in and i run an AL6 MSD ignition box. when i was was splicing some of the wire to make them long enough i took out a resister that runs off the alternator. its about the size of a peice of rice and comes with your ignition box.