You don't need to tap into the exhaust system. That is just a way to create vacuum to the can. The more common way to run a catch can is to just have the breather lines (one or both) run to the can and then have a filter on top to let gases escape.
1999 Eclipse GS Built motor Hahn 16G Turbo w/ FMIC Hahn Stage 5 Portfueler (270's & 500's) Zeitronix Zt-2 wideband w/ 3.5bar MAP 3" SS Turbo Back CM Stage 4 Clutch and Fidanza Flywheel Baer Big Brake Kit