How do I get to Plant 42? I have the Closet Key and AR with infin magmum and health but am at a loss of how to get to Plant 42. My friend did it but he won't tell me. Any walkthrough?

its in the gaurd house.

Go to the courtyard that is after you get the four medals. You will need the crank found in the last room before the courtyard. Go straight and you the crank to lower the water. Next continue down to reach the guardhouse. Get the dorm key and get the code in the room with red doors. You will need it for the V-Jolt. In dorm 002 climb the ladder and head to the control room with the key found in one of the bathrooms. Use V-Jolt on the roots and then go to dorm003 and put the red book on the bookcase. The next door is Plant 42. Make sure you have the flame rounds if you're Jill if not just shoot it with the shotgun