Never owned a model T but did have a model A. In the A the gas tank made up the top of the fire wall and the top of the dash board. So that really made it in side the car.the Model T Ford had one thing in common. Their fuel tank was mounted on the engine side of the firewall. Really in your lap!
Also had a couple of Jeeps, CJ2A and a CJ3B, they had the gas tank right under the drivers seat,
https://www.motortrend.com/how-to/0805sr-ford-model-a-fuel-tank-dashboard-cowl-assembly/

