seat mount

I can't seem to get the back part of the seat to click in. No matter how hard I push down on the seat or push on the little release lever on the right-hand side, it won't clip in. I've tried removing the rubber spacers on the bottom of the seat to make sure it's going down far enough and I tried...

I'm replacing the stock seat with a solo seat from TC Bros Choppers. The guy mounting it says the battery is about 1 inch too high so will have to shim up somehow. They offer a pivot front mounting bracket which costs almost as much as the seat but will at least give me battery/fuse access...