I know that sometimes the situation doesn't allow you to sell or make sense because of the loss you might take. I would suggest you take a look at what you have invested in the truck and how much you might be able to recover if you sold at fair market value. You will probably take a loss, but what you need to consider is if that loss is close to what you might spend to build the truck the way you want it. You may be surprised to find in the end it works out about the same, and doesn't require the labor.
It's hard to put a value on sentiment, but I have learned for the right money almost anything can be replaced....
