Let $X$ be a connected scheme,$\pi_1(X,\bar{x})$ its étale fundamental group for some geometric point $\bar{x} : Spec(K) \rightarrow X$ and $E = \pi_1(X,\bar{x})/N$ a finite quotient of $\pi_1(X,\bar{x})$

I am looking for book or paper describing the explicit construction of the Galois cover $Y \rightarrow X$ corresponding to $E$ other than Grothendieck's SGA or Tamas Szamuely's book