If the bed is damaged, with a blown HG, you aren't likely to get more than a $3-400 for it as it is, and not much/if any more if you part it out. If the bed isn't a loss, you might get $800 as it is. However if you didn't drive it much after the HG went, you should be able to fix it yourself for around $300 with a new t-chain. This will increase the trucks value atleast another $1000-1500. If you have the tools/or access to them, you should be able to have it done in a day or two, i.e., start Friday after work and you should be driving it on Sunday, providing the only thing wrong is the HG. If it overheated on you you should have the head ckecked.