I don't think I can make it to Hong Kong
I will however give you a peice of advice. Anyone who told you that the finance company would just repo the truck and it would be gone is lying to you. I know underhanded car salesmen and finance guys that will tell customers **** like that.
First, they will come take the truck. They own it.
That does not mean that you're off the hook for the payments. Like others have said, with the mods you've done they could never get out from underneath it. If they decided to hold you liable, they can seize the truck, get what they can for it on the market or in scrap and hold you liable for either the entire debt, or what they still have outstanding after the sale.
If they do this, then one of two things can happen.
They can come after you for the money, have liens put against any property you have or garnish any wages until they get their cash.
OR
They can charge off the entire amount as bad debt and collect from their insurance to recoup their losses.
Either way is bad.
If they come after your assets or your wages, then not only will you be strapped for cash, you'll find yourself in a position where you would have to sell belongings and property to satisfy the liens. Any amount they garnish your wages will be more than $422 a month. They'll look at your absolute expenses (mortgage or rent, basic utilities) and they could possibly take damn near the rest to pay off the bad debt as quickly as possible. No court would have much pity on you either because you took a vehicle you did not own outright, modified it and destroyed it, then dumped it on the lienholder. They'll make an example of you)
If they charge off the debt, then the only thing worse that can happen to your credit is a bankruptcy. Forget about getting ANY credit (cards, car, home, medical or car insurance, cell phones, any utilities) for 5 years or more. They just wont do it.
Now, the question is which way would they go. They would probably go the path of least resistance. Since you dont seem to have any assets worth any value other than the truck, they've already taken that, they'll charge off the debt and collect from their insurers.
I would refinance it (if you can get the credit) and live with it...
**** like this can destroy your future. Even after the charge off is no longer active on your record, mortgage companies, car loan companies etc can pull a history and see it, like a bankruptcy. VERY few Americans have charge offs or bankruptcies and it makes you look like a terrible credit risk.