Cache is not at posted coordinates
To solve this puzzle, follow these directions. You will need scissors and tape (preferably transparent).
- Print out this document.
- Cut out the rectangle from the page.
- Place the page face-down (coloured side down), and fold creases along all of the solid black lines (vertically and horizontally).

- Cut along the heavy dotted lines.

- Place the page face-down again, and fold the left middle section (consisting of four squares) out toward the left edge of the paper. You should see four coloured squares on the left side (2x2), and a gap 2 squares wide and 2 squares high in the middle.

- On the left edge, tape the two centre squares (that you just folded over) to the squares behind them, by wrapping a piece of tape around from front to back. This should create a "fold" of tape connecting the front to the back.
- Repeat the last two steps on the right side.

- You now have a section 4 squares high and 2 squares wide on the left side of the paper. Fold that section in toward the centre so that it lines up with the centre of the paper. Put a piece of tape flat across the top and bottom squares along the center of the paper, so the former left edge is now connected.

- Do the same with the right edge, bring it to the centre and taping flat across the centre line on top of the former left edge.

- Your construction is now complete! Carefully open up the individual cubes of the construction until you have a 3-dimensional object.

Once you have constructed your object, play around with it to discover the final coordinates of this cache!
This video might help with the instructions for those who are more visually-minded. Note that the initial cutting and folding in the video is just to get a rectangular grid like you already have.
This site might help with the solving, for those who don't like doing base-conversion in their heads...
Again, for the mathematically challenged, this site might help with formatting your coordinates.
And, finally, you can check your solution here.
Happy solving!

Congratulations to Jean Déniche on being First to Find!