So I just finished installing a used authentic mugen hardtop. I received the instructions in Japanese but still managed to install it. The minor problem I'm having; there is a small gap in the rear when it's latched all around. The gap on the sides seem ok and the front sits slighty lower than the top of the windshield. There is also wind noise when accelerating over 60mph, nothing dramatic but noticable. I'm curious to how much of a gap you guys have on the rear when the mugen top is latched on. Can you insert a #2 pencil in the gap?

Also, what do you use to keep the rear window clean and scratch free? Is windex safe or harmful?