Hilary Doyle found a diagram in the German archives revealing that there was a proposal to fit the Tiger I with low-profile hatches similar to those on the Tiger II. The diagram is a mere sketch but it gives exact dimensions.
I used the sketch to make these drawings. They show that the new hatches are considerably further inboard than the normal ones - 500mm from the center line rather than 900mm. It was always an annoyance in the Tiger 1 that these hatches were not over the crewmen's heads. This was necessary because they lifted to open. The new hatches would have simply rotated to the side, without fouling the turret.
Here, I have made a partial model of the hull top toshow what the hatches would have looked like. I used handles and hinges from the Tiger-II.