Help with Second Gen RX 7 Idiot light panel and buzzer

I finally finished getting my track toy 2.0 back together and have a buzzer that won't go away. I swapped the engine over from the last car and it runs fine. In the old car I removed the idiot light cluster altogether. In this car I kept it, none of the lights are lit but as soon as I turn the key the buzzer is activated. I am running an aftermarket oil pressure gauge and am using the appropriate sensor for the gauge. The factory gauge in the dash cluster in not connected to anything and I think that may be the issue. Does anyone know what kind of a signal I should be getting from the factory sender? Maybe I can just ground it out or put a resistor on it? hoping to get it out on track at the end of the month and don't want to listen to the buzzer all day long. Thanks.

Mine buzzes when the coolant level is low. There's a coolant level sensor connector at the top of the radiator.

That buzzer is your low coolant, low oil and redline warning. I'm with 1988RedT2, check your coolant level. I forget if it buzzes if the sensor is disconnected or not, I think not, though.

Thanks for the replies. After posting this I realized it probably wasn't the oil pressure gauge as I had the same set up in the other car. This morning I went out to ground the low coolant signal and noticed the buzzer comes on with just the key in the on position and that it is a different tone than the buzzer that comes on when an idiot light comes on. The idiot light buzzer is a louder and deeper sound, it came on while testing this AM. The constant one is a little higher pitched. Where it comes on before the engine is even started it must be something outside the engine bay. Maybe a seatbelt issue, I have the interior gutted. The last car was only partially gutted but I think I had all the seatbelt stuff removed as well (that car has been gone a year now). At this point where I know it is not an engine related item I may hunt for it and remove it. Any other thoughts are welcome.

Is the power steering computer hooked up? Does the car have power steering? Did you take off the steering wheel?

I had the same issue. It was because I depowered the steering and left the computer under the column hooked up.

Thia car did have power steering but I moved the manual rack from the other car. Any idea where the box is above the column or what it looks like? Does it just need to be unplugged or does something need to be done, resistor/ ground something to make it not signal the buzzer?

Unplug it. It is right under the column to the left iirc.