when I put the key in and turn just a little I can take the key out and still turn the ignition. Im sure this can cause battery drain. Do I have to replace ignition in the colum where you put the key? Also I think I have to change out my light switch. Please dont tell me I have to remove the dash? I have a 80 vette

You should replace the key cylinder for safety reasons, if nothing else. The way it is now will make it easy for someone to steal the car.

To replace the headlight switch, you do need to pull the driver side dash panel/cluster out, but not necessarily all the way off. If you take the top dash pad off, you may be able to remove the light switch from there, without having to pull the dash cluster(speedo/tach).

    I just replaced mine on my 80. I removed the speedo cluster which made it a lot easier. If you have very thin womanly hands you may be able to snake it up from the bottom in order to push the button to release the knob.  If you pull the cluster unbolt the 2 bolts holding the steering column and drop it down. If there are shims remember where they go.