hmmmm ... very interesting .....
I'm sure your answers will come easy from calling Donovan.
It does sound like it is a wet sump block converted to dry sump. If you want to find out on your own pull the rear main off and make sure you it has the galley going over to the filter boss. I will bet it does. Its probably plugged off under the main cap. If it was a dry sump block I dont think it would have the oil filter provision.