There are general materials available online, however every company makes up their own aircraft limitations. In my opinion, It would be a detriment to your training to have to relearn the same things with different numbers in class. Just be sure you know how to read plates and brief/fly approaches without any hiccups. Some people that didn't fly ifr much ran into brick walls, because it's enough to be learning a new (and in most cases more complicated) airplane without turning it into a basic instrument lesson.

They provide you with all the info/materials you need. You will have every opportunity to be successful if you have a good attitude and put in the effort.