“but what about a transport that loses transport capacity when armed such as a jeep?”
That depends on how many armoured car selection slots you have in the selector you’re using – see p 153, Force Selection, Force Selection Rules, seventh para.
Basically, if your transport takes an option that removes it’s transport capacity and it’s wheeled AND damage value 7+ or worse, it becomes an armoured car for selection. If it’s not wheeled OR it’s damage value 8+ or better, it becomes a SP gun for selection (taking the slot you’d usually use for a tank).
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