oil catch can

So I decided to go with the Provent 200 for my HDJ81 and if anyone is looking to get one as well, just order all the hardware online. The Provent itself comes with nothing if ordered on amazon. So I found some threaded 19mm adapters from AU and hose that I'm waiting on now. Does anyone have some...

I'm asking because I'm going for an oil catch can, but they come with different hose sizes.... Thanks in advance!!

Is anyone on 'Mud using an oil catch can (especially the SC guys)? Is this something worth doing? I know for a fact I'm getting oil in my intake with a 6 psi SC...