open market value won't make much difference unless you have it insured for that value beforehand. the adjuster will look at your vehicle, assess the damage and repair total (more than likely on a laptop while you wait), withdraw a value from the same computer, deduct for high mileage, previous dents or damage, etc. he will then tell you what your truck is worth and what it takes to fix it. depending on the company, a percentage of damage to value will determine if it totals or not (looking at the pics, i think it will). he'll cut you a check for the total amount and tell you where to drove it too. or he'll cut you a check , reduced by the salvage value (in the same computer) and you keep it.
i hate to be the bearer of bad news but i work around bodyshops all day long. you will not get market value from the adjuster. his laptop is bible to him. you can argue and get a hundred here or there, but not much else. it's not the job of the other persons insurance to over insure your vehicle. its you and your insurance company's to make sure you are covered for replacement value. i know that sounds harsh but dealing with insurance usually is. i learned this when my brothers 69 charger was rear ended 3 years ago.
my advise to you is if your not happy with what they'll give you, don't accept the check. it probably won't be worth getting laywers involved, and the insurance company knows this. get as much as you can without sueing and move on.
sorry to see that