Polyurethane Spring Perch Bushings -- Is This Right?

Ok so I've installed the polyurethane spring perch bushings in the front of my 66, and am wondering if I followed the directions closely enough... I pressed the bushings into the sleeve and greased the slider into the bushings. In fact I've driven the car and it feels great (and since I cut the front springs the height is just right too).

But what's the deal with the black tabs on one end of the perch sleeve? They obviously keep the sleeve located. Is it Ok to leave those there or was I supposed to grind them down a bit? The directions weren't clear enough for me.

Thanks!!!

Thanks! Well, I understood that part about the end of the spring fitting into the pocket. That wasn't changed and it's as tight in there as it can get. I was wondering about the black metal tabs that are touching the back of the polyurethane bushing shoulder in the photo. I'm probably making more of this than need be, but I always second-guess things unless I'm certain...