To determine the coordinates for the final, you will need to look at this archway in detail.
For both coordinates, use the left side of the archway when facing south.
The final can be found at:
N 39 3A.BCD W 104 5E.FGH
A = Red - Blue
B = Orange
CD = Blue x Orange x Orange - Red + Orange
E = Red
F = Orange
GH = Red x Blue - Orange - Blue
Checksum for all 15 digits is 58.
Both stages are available at all times. You may have to struggle with bouncing coordinates at the final. The difficulty reflects this.