I am having a boost gauge fitted to my Twin Turbo Legacy. Is the fitting of the boost gauge any different from the single turbo imprezas? Don't laugh...but will I need two gauges, one for each turbo?

If only one gauge is connected to read the boost pressure in two turbo's what sort of reading should I be expecting? A certain pressure when the small turbo is on boost, then a sudden drop followed by a build up to higher boost when the boost is built up on the larger turbo whilst the small turbo slows down?