You should sell it for as much as you can get. Or sell it to me, cheap!
The first question is, Do you
have to sell it? If you don't need to get out of it to get into your next truck, you can hold out for more money, even to the point of not selling.
If you are going to sell it, put it on Ebay with your favorite method (Reserve, No Reserve, Buy It Now, Best Offer... ) as many times as it takes to get at least your minimum dollar.
If you don't have to sell it (or at least not quickly, I would approach it like this:
1. Add up the market price of the truck and all the accessories.
2. Increase the value for hard to find items everyone wants.
3. Decrease the value for accessories only you care about.
4. Decide if you would take a discount because the new owner will not get the "buy it new off the lot" or "order and wait for it" experience.
5. Decide if you will command a premium because the new owner will not have to spend hours waiting around for accessories to be installed and can quiz you on exactly how everything works.
If you want someone on this forum to try to guess what starting bid would be a good one, I would think there needs to be some more information, like how much you have in it.
Hopefully, someone will PM you and offer to buy it with a price you can live with. That may be what you are after, anyway. :-laf
Good luck!