Merkava.

[Marcello]

Originally Posted by kevineduguay1

From another site....
This arrangement also creates an otherwise unused space in the rear of the tank that allows increased storage capacity, as well as a rear entrance to the main crew cabinet allowing easy access even under enemy fire. This allows the tank to be used as a platform for medical disembarkation, a forward command and control station, and an armored personnel carrier.

Putting the engine to the front does not automatically create any new space. By itself it only makes possible rear access and the creation of a multipurpose rear compartment.
But it a design choice which comes with trade offs.
Otherwise a simple "engine to the front" configuration would result in something like this:


Not much in the way of storage space, even if a rear hatch was added.

The Centauro has a configuration similar to Merkava: front engine, rear turret and rear hull access. But adding troops there means reducing ammo (or creating a lenghtened version, as it was done).