Fairly tight to the case.  If you just open it (and don't  put it around on the side completely out of the way), you would need 1 1/4 inches of clearance (I just measured), over an above the width of the case (8 1/2 inches).  To put it completely out of the way, you need about 4 inches.  So you could try it by just opening it sufficiently to use the items (and there is no problem with that); if you do not like that you could remove it (but it does keep dust out of the drives!).

It swings tight to 90 degrees, then swings wide on the double hinge to tuck back against the side of the chassis. Opened 90 degrees isn't a good idea as some one may bump it and .......You can try open and tucked, work with the 90 degrees or just remove the door and double hinge assembly. I sure hope you have some room in there to circulate air!