I actually remember being pulled from the stands once to umpire a LL game, we had actually just moved to town and my son joined the local LL 13-14 boys and the umps did not show they asked if anyone had experience and I volunteered along with another dad and we did a pretty decent job considering I had to call the game from behind the pitchers mound
I've had to ump and coach LL games at the same time. Honestly I prefer calling balls and strikes from behind the rubber rather than behind the plate..