The car sounds like a decent starting point for a 440 tribute car. With out pictures pricing for a project car will range from $5/6 thousand dollars all the way up to 15/20 thousand dollars depending on a LOT of different variables. As you described it, it sounds like a 5/10 thousand dollar car.
As for what they are worth when done, again depend on a LOT of things, such as the level of details put into any particular vehicle. A true 440 car will out value a \6 changed to a 440 almost every time. tribute cars with 440 seems to fall into the 20/40 thousand dollar range.