Some thoughts on how APCs could be handled:

An unit designated as an armored personnel carrier (APC) is treated as an AFV for all purposes. In addition, it is capable of transporting infantry across the battlefield.

To embark on an APC unit, an infantry unit must be adjacent to the APC unit, and both units must have "Special" order markers. When activated, the infantry unit is removed from the board, and is now considered to be carried by the APC unit. The APC unit's order marker is discarded (i.e. both units are "activated" at the cost of 1 CP).

An APC unit may only carry one infantry unit at a time. The number of infantry elements carried may not exceed the number of APC elements: e.g. a unit of 3 APC elements may carry one infantry unit with no more than 3 elements.

To disembark from an APC unit, the APC unit must have a "Special" order marker. When activated, the APC unit remains in place, and the carried infantry unit is placed in an adjacent hex. An infantry unit may not disembark into a hex containing another unit and/or impassible terrain.