My keyminder buzzer (w/i the horn relay) works, but it works whether the keys are in the ignition or not when the driver's door is open. Any thots on how I might correct this problem?

Thank you,
Sam

There is a switch with a set of contacts the fits in a hole under the directional light switch.

You would need to remove the steering wheel, lock plate and turn signal switch to get to it.

Here is a link to a couple pages of a Saginaw Steering Gear service document. It is quite complete on trouble shooting your key buzzer problem.
http://www.corvettefaq.com/c3/KeyBuzzerDiagnosis.doc

Even though it is posted on the corvettefaq websight, it is valid for your Chevelle. I assume that you have a 1969 or later vehicle.
Good luck,
JIML82

Thanks for the guidance. Will let you know.

Sam