8. In an $8 \times 6$ grid, each cell is colored one of four colors: red, blue, yellow, or green. If each $2 \times 2$ subgrid contains exactly one cell of each color, it is called a "balanced" coloring. The number of different "balanced" colorings is $\qquad$ kinds.
As shown in the figure, the four squares in the upper left corner can be colored in any of 4! ways, then the squares in the subsequent columns of the first two rows can be colored in $2^{6}$ ways. After the first two rows are colored, the coloring method for the rest is uniquely determined; similarly, the squares in the subsequent rows of the first two columns can be colored in $2^{4}$ ways, and after the first two columns are colored, the coloring method for the rest is also uniquely determined. 

Among these, the 24 coloring methods that completely replicate the upper left corner are counted repeatedly, so the number of different "balanced" coloring methods is $24\left(2^{6}+2^{4}-1\right)=1896$.

\begin{tabular}{|l|l|l|l|l|l|l|l|}
\hline 4 & 3 & 2 & 1 & 4 & 1 & 2 & 3 \\
\hline 2 & 1 & 4 & 3 & 2 & 3 & 4 & 1 \\
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\hline
\end{tabular}