Tamagawa number conjecture for $SL_n$ over a function field

Let $F=\mathbb C(X)$ be the function field associated with the Riemann surface $M$, let $\mathbb A$ be its adelic ring, and let $\mathbb K$ be the specified maximal compact subgroup. Let $\tau$ denote the Tamagawa measure and $\mathrm{m}(\mathbb K)$ the mass of $\mathbb K$. Tamagawa number conjecture. There exist natural measures such that

$$\tau\big(SL_n(F)\backslash SL_n(\mathbb A)\big)=1$$

and

$$\mathrm{m}(\mathbb K)=\widehat\zeta_M(1)\widehat\zeta_M(2)\cdots\widehat\zeta_M(n).$$

The conjecture seeks a Tamagawa-number normalization and a zeta-value formula for the maximal compact subgroup. The source gives no resolution.