Down here in San Antonio TX, dealers are marking $10K to $15K off Ram diesels AND 84 months 0% interest with 90 days delay for first payment. Check online as well to see if there are any other dealers in the area you are shopping to compete for your business, if no one close, find comparable Ford or Chevy to leverage the price. No competition can reduce chances of making a great deal. Even find a new one on Ebay and use it for dealing. I actually purchased a new Ram 4500 on Ebay in 2009.
You should be in great dealing position, no trade and a check from the ins company for your wreck.
Cheers, Ron