Your problems with the Academy kit won't be easily solved. About half the turret internal parts are simply not present in the kit, and the rest are misshapen and poorly scaled.
For example, take the two strengthening beams on the turret roof. Academy give them an I-beam profile; in reality they were simply flat. Academy place them offset to one side, but in reality they were equally spaced from the turret center line.
And that leads to another problem in the Academy kit. The turret has a misshapen plan outline. It puts the gun off-center, which is wrong. This isn't noticeable from outside if you don't look for it, but it throws everything off on the inside.
Here's a plan view of a Mid Tiger turret. If you have Academy's Early kit, a few parts would be different, but most would be the same and in the same places.
Compare this to your kit and you'll see the scale of the problems.
David