I hoped, someone else could figure it out and recreate a similar blueprint to the shown one ^.^
However, i have to agree with MostHostLA, it would make more sense to let the perspective intact and not compensate for it. Instead why not use it to your advantage? Puzzles that include perspective are way to rare. The last game, i have played, that uses perspective, was “Indiana Jones and the fate of Atlantis” (at one point you have to use survey equipment with a certain piece of a buillding to home on the location of a hidden artifact). And that gameis from the last millenium Still awesome game.
Also, if you do it right, you can create several marks in your game, that become only visible from a certain point of view. Like this one here with those pillars and their paintings, that, watched from the correct position, reveal Kong. At the 1.10 minute mark:
So you could have big marks for general directions and smaller ones, once you are closer to your treasure area.