Hi Brad, sorry missed your first posting - only reference I can find in workshop manual to weights is where to look for weight information on the chassis data plate -but states for UK only. Not so helpful for you in Oz unless you have equivalent chassis plates or van spent some time on the road in UK first before travelling. I do have owners manual as well but bit buried at the mo I'm afraid:I
There are some lorry weighing stations dotted about the landscape, if you have one nearby am guessing you could pop down and get van on the scales[?][8)]
Sorry can't be more help - afraid I don't have a 2500 to look on my chassis plate but maybe someone else has one[?] - good luck