About this detail of the Tiger
Although this tank was never completed, Krupp did build at least one armour shell for its turret. Photographs show that this turret had two large pistol ports in the back, similar to those later used on the Tiger E.
Revosys provide these ports in their kit. On the inside of the ports they give us part K12, a plug. They have copied this part from the Tiger E, speculating that the VK3601 ports would be the same as the Tiger ports inside and out.
But on the Tiger, this plug was not kept in the port, the way Revosys' instructions tell you. This plug was to seal the port for underwater travel; a Tiger's two plugs were usually stored in its hull and might never be used at all.
The VK3601 was not specified to have underwater travel capability like the Tiger, therefore it would not have carried these plugs. You should not use part K12.