[special-K]

First, have you gotten back to the guy and given him a chance to make it right... take it back as misrepresented? If you haven't and you go ahead and do that, put a lot of thought into how you will handle it first. You need to be assertive yet not threatening, at least not at first. You can make indirect mention of taking it to another level and let him know you are no push-over. Be tough but not nasty.

I'm not sure you didn't screw yourself. You said you were hasty and didn't check out all the obvious things to check. You didn't check the frame for being shortened and you didn't look at the VIN, or at least you didn't know the third digit being a 2 means C/20. With any vehicle purchase it is rule #1 to compare VIN on vehicle and title. You may have been too upset to mention in your post, but I don't see where you say what lies the man told you. Did you ask all the pertinent questions to verify the truck wasn't shortened/converted? Once you build a shortbed out of a longbed it is a shortbed. Is it a factory shortbed? That question needs to be asked or vehicle needs to be checked.

I'm not saying the guy isn't shady for leaving it to you, in your passion, to convince yourself it was a true shortbed. But the world is full of people like that and it is up to you to protect yourself from them. It's a slick way to do business to offer as little information as possible and leave it up to the buyer to ask, so they can later say "I didn't lie to him" about the important questions the buyer neglects to ask. You know the seller is standing there hoping the deal breaker question never gets asked and just can't wait to here the buyer say "I'll take it". Very corrupt and all too common.

As far as help goes, you can buy a frame pretty cheap. Longbed frames aren't too hard to come across. I don't know if you can do the work better yourself or you just know bad work when you see it. You need to post up pictures. We may see a way to make it right. It will be a lot of work you weren't counting on no matter how you go about it. Paying to have a longbed cut down or yours made right shouldn't be too awful. But hopefully that's something you can do.