How much is it worth?

I think you need to find someone you know who's looking to build one, and try to get them into it. Unfortunately my opinion is it's worth somewhere around $3500 as it sits. I think (basing on my personal experience) you may find that the only buyers are not willing to pay even that much, and I'm sure by totalling the parts/labor you have it's closer to $5500. It might be better if you need cash to sell the heads, shortblock, intake, carb, etc seperately. I find it easier to get a better return by breaking it up.