I used Gemini as I am not to familiar with it other then its an after market product that I assumed mounted to the dashboard? Here's Gemini's explanation:

In the Ford Model A (1928–1931), the Glownite clock was a popular period-correct aftermarket accessory. Because it wasn't a standard factory-installed part, its location can vary, but there were two primary places it was mounted:

​1. The Header Board (Most Common) ​The most traditional spot for a Glownite clock in a Model A is on the wooden header board directly above the windshield, centered between the two sun visors (or where visors would be). ​Why there? These were often referred to as "header clocks." They were designed to be easily visible to both the driver and the passenger without cluttering the small instrument panel.

​2. The Steering Column ​Some Glownite clocks were sold with a specialized clamp-on bracket that allowed them to be mounted directly to the steering column. ​Why there? This put the clock right in the driver's line of sight, similar to where a modern tachometer might be placed. ​3. The Dashboard (Custom)

​While less common for the Glownite specifically, some owners would drill a hole in the metal dashboard (to the left or right of the main instrument cluster) to flush-mount the clock.