one way to use the extra slots is to replicate models but change the damage model so that a line of lorries, when destroyed, would show a whole range of different damage models... gets rid of the repetitive nature of the damaged models.
Yep, we still have those multiple damage models in my folder at the Gen's server. In a few cases we have three of the same lorry ( um, that's a truck in American English ) with different damage models.
Ya' know, I'm wondering about the possibility of adding a carrier too.