For the polynomial $P(x) = 2x^4 - 4x^3 + 3x^2 - 8x + 6$, identify the coefficients of $x^4$, $x^3$, $x^2$, $x$, and the constant term. Then, find the sum of the squares of these coefficients. Let's think step by step and output the final answer within \boxed{}.
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