It's interesting that no one seems to have a problem installing the HO 4"s in an e90. I know there's "supposed" to be plenty of room. Unfortunately, mine hit the window on both sides. Wasn't obvious until I rolled up the windows.
The driver side just barely rubs the window enough to see the door panel move. The pass side was close enough to tear the vapor barrier.
Looks like I'm just going to install them from the front like you have above. Just a heads up for others. I really don't know why mine are hitting. I'm using the same setup as VPElectricity has.