Idiot light threads?

[ravege]

Previous owner installed a mechanical temp gauge putting the sender in the idiot light location to the left of the thermostat. I'm tossing the temp gauge, but don't have the original sender, I'd like to just put a set screw/plug there, what are the threads/fitting size?

 

[Boxcars]

The same size as the bushing you took out?

 

[87GNSteve]

I believe its 3/8 NPT

 

[ravege]

Thanks Steve!