Been a while since I took one apart ...
That flower looking thing on the opposite side, I think it has to come off. IIRC, the petals have to be spread a bit and then it pulls off. A socket might works well here.
Then that arm should pull out and the lever up.
I just don't recall having to do any of this though. IIRC mine had a C clip I pulled and everything came apart.
I'll go look in a bit here.
Don't "think outside the box".
There is no box.