It was a pretty easy job, but it just doesn't feel secure and the tank feels like it's leaning forward, like it needs to be secured to the wall or something. The wax ring that came with it was too thin, so the bowl was resting on the tile without the ring making contact. So I stack another one on there, one without a flange, and that seemed to work. Though the bowl still feels a little wobbly. I don't want to cinch down those wing nuts anymore, as they feel like they're gonna bend the washers or crack the porcelain.
The tank appears to sit on top of the large gasket that goes on the bottom of it and on top of the bowl. I've cinched those wing nuts down very tight and the tank really leans forward, such that even pressing one of the flush buttons makes it wobble. What am I'm doing wrong here? Hard to see in this photo. I'm wondering if I need to redo the tank, such that it leans farther back on the gasket before cinching down the bolts.