Their 8" gunned sub had never seen the Pacific, it was sunk near Bermudas on its way there by collision with freighter Thomson Lykes
BTW I can't imagine a submarine firing a midship salvo from 2 8" cannons as Surcouf was meant to do... It must have looked like this
http://www.youtube.com/watch?v=A6XpNz7QpBs&feature=related