There are 4 shapes on a 8x8 grid. Which shape is closest to the cyan right_triangle in terms of Manhattan distance? The final answer is the grid position of the closest shape like (row_index, column_index).
<think>Target shape: cyan right_triangle at (1, 4)
Distance from target shape to brown trapezoid at (6, 4): 5
Distance from target shape to blue square at (3, 6): 4
Distance from target shape to orange right_triangle at (6, 3): 6
Closest shape is the blue square at (3, 6) with distance 4</think>

<answer>(3, 6)</answer>