I know this topic has been kicked around quite a bit, but I can't seem to find the answer I need. I have a 69 Chevelle. At one time it was a column shift automatic, but was converted 10 years ago to a floor shift automatic. The steering column appears to be correct for a floor shift with a neutral safety switch installed on the top of the column. It wasn't working, so I bought the necessary switch and wiring harnesses for a floor shift auto and installed it. I removed the NSS on the column and tried to start the car. Nothing. At this point, I put the old neutral safety switch back on the column and plugged it in. It still doesn't work, but the car will start. What am I missing. I would like to use the NSS that I installed on the floor shifter. I thought once I pulled the old switch and wired up the new one, I would be fine. Apparently not. Any ideas what I am doing wrong?

is the back drive hooked up if it is you will see the columb rotate right where it comes out of the dash.

I checked the linkage rod in the engine compartment and nothing is attached to that. I am assuming that the back drive linkage would have been attached to the linkage rod.

Did you bridge the two old wires that used to be connected to your old NSS? They have to be connected if you eliminate the old switch. They are still integral to the "hot" wire that goes from your ignition switch to the "S" terminal on your starter solenoid.

Somewhere along the line I would assume that you tapped into one or the other of those wires for your new NSS. If you attached your new NSS to the upstream ignition wire coming from the ignition switch you should have had no problem. Conversely if you attached your new NSS to the downstream wire coming out of your old NSS you would have no ignition current and experience the issue you are now having..

Yes you are correct that linkage runs off the tranny to move the columb now hook your switch back up like you had it and turn the columb by hand near the dash and see what happens.

I am not sure what you mean by bridging the old wires. I disconnected wiring harness from the old NSS, two wires for the NSS and two wires for the back up lights. I connected an extension wiring harness to those connections, which was then connected to the wiring harness going to the floor shifter NSS. When I do that, I get no ignition. If I take the old wiring harness and plug it back into the old NSS on the column, the car will start.

Basically the 2 wires from your old NSS carry 12v to the starter solenoid.
If they are not connected, no power to the starter solenoid.

The column moves from Park to drive to make or break the connections in that switch.

Check to see if you don't have a switch hanging off the tranny.