There are 2 shapes on a 8x8 grid. Which shape is closest to the red square 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 square at (4, 2)
Distance from target shape to gray rectangle at (6, 3): 3
Closest shape is the gray rectangle at (6, 3) with distance 3</think>

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