Followed Chuck's link, excellent way to do the hinge!

Makes me think of the same method, but leaving the lower hinge wing to join up with the boxes back (half lap, spline?)

Then the pin could be installed before putting on the lid.
(I always hate trying to install small bits to conceal a cut unless I have easy access for a hammer 8^)

Easily beats dealing with standard box hinge installs and looks so much better!