My opinion is and it's not worth much is that upgrades do not increase value. Condition is everything and it appears in good shape. It'll never be worth more than a new one would cost. Best thing to do is find a price you would be comfortable selling it for and list it. If you don't get any bites then it is priced to high and you will have to adjust the price. Ultimately the buyer will be the one who determines what it's worth. Everyone else can guess or give a ballpark, but if they are not interested in buying it, they are just guessing.
As far as parting it out, you may get more that way, but it will likely take much longer to sell all of it compared to complete.