There are 3 shapes on a 9x9 grid. Which shape is closest to the red rectangle in terms of Manhattan distance? The final answer is the grid position of the closest shape like (row_index, column_index).
<think>Target shape: red rectangle at (8, 6)
Distance from target shape to yellow right_triangle at (7, 6): 1
Distance from target shape to green rectangle at (6, 3): 5
Closest shape is the yellow right_triangle at (7, 6) with distance 1</think>

<answer>(7, 6)</answer>