Ins. Co. wants to total work truck W/equipment

I have a 2001 Chevy 1 ton work Van that was in excellent condition. Which, has a lot of equipment installed that runs off the engine of the van. The ins, Co. received a quote of 7800.00 to repair the van. The Van is worth 5500.00 with out the equipment installed. I did not insure the equipment or loss of use.

Here is the question. Can the ins. Co. force me to total the van just because the damage over exceeds the value? There is nothing wrong with the mechanics, the damage is cosmetic. I am still driving and using it to service my customers. It will be costly for me to find a compatible 1 ton van and to switch out the equipment. It is my sole income and I would be down two weeks. Does not the Ins. co. have an obligation to return me back to the state pre-accident or compensate me.
What I want to know, do I have the right to demand they pay me the Value of the Van and also keep the van? I can fix it myself and have no loss of work. There saying now if I want the 5500.00 they will need the van or I could keep the van minus the Salvage cost. Also, If I kept the van minus slavage I would have I could not drive it until I had it inspected by DOT . That does not seem right. The van is very serviceable.

If they refuse would I have a case to receive the 5500.00 and keep the van so I have not down time?
I have been with State farm for over 25 years and only 3 small claims less than 3000.00.

Thanks for your advice and time.

No--you get the van if you want, or the payment; you cannot force them to allow both--but you can certainly try and ask! They may agree.