ignition switch engages starter after engine is running???

[davecobra]

Well let see if I can answer this good, I am not a good typist, I just finished puting the wiring harness in the car with a new ing switch and soleniod, two days later after setting the valves and checking the rest of the lights and guages I notice the starter trying to engage, the first time I just turn the switch on and not to the start position and the starter engage and started the car with the starter still grinding, I shut it off and tried it again and it worked fine, after turning the switch off and on several more times it again started in just the on position and stayed engaged. I thought bad switch or soleniod, so went down to Napa and bought new switch and soleniod, installed, worked great for about week, then yesterday while moving the car out of the garage it did it again, this time I thought it had ruined the ring gear as it hid hard, all I did was turn the switch on to turn the radio on and it started and the started stayed engaged.
Now as the wiring goes the ign switch is a 4 pole generic switch it has an ign pole, sol pole, acc pole, batt pole. The hook up is simple, Batt lead to batt, ing to ing , sol to sol and acc to acc. No special things add, I do run a MSD and electric fuel pump and fans. On the soleniod I have a wire that runs from the start terminal to the ing side of the switch so that when it is in crank mode it will give power to the msd. I do not think I have two bad switchs in a row but who know?????
As far a checking with the lights I did that and it is getting power to the soleniod sometimes just turning the switch on, it would appear to be a bad switch, but in the back of my mind I think something else is causing it.
Hope this help you to help me.
Thanks David