According to GM, current draw on the vehicle should drop below 35ma. There will be draws measured for the radio (clock) and ECM (memory). If you have any add on accessories such as amp, alarm, keyless entry, I would suggest disconnecting them first.
To trace this draw, first make sure all accessories are turned off. Nothing in the lighter socket. Under hood light turned off (slightly bend bracket to turn light off, if it won't turn off like that, it's bad).
Still have draw? Disconnect driver's door jam switch to disable courtesy lights when driver's door is open. Start pulling fuses one at a time to isolate which circuit has the draw. Again expect to see a slight drop when the ECM and the radio battery feed fuses are pulled. Each vehicle has these listed under different names so check your owner's manual. When your major drop on amperage is isolated, you will have to check all componants on that circuit. It could be a componant gone bad, a sticky relay or evan a wire shorted to ground.
good luck