I'd start by totalling all the parts up, plus price of the truck....that would be the lowest i'd sell for, unless i was really strapped for cash.
Then, figure all your hours you have into it, and multiply by 50 cents
Just kidding, you should be able to come up with some figure for your labor...which would have to be appealing for someone who's thinking of having the same thing done at a shop.
Since it's all new and never hit the road, and assuming all the work was done correctly, you should at least be able to recoup the money you have into it plus some on top for your time.
Good luck, looks like a heck of a good start for someone.