I have a Stormrider full front. You do need to trim the edges in some parts and fill in the edges at other parts. It is not perfect, but what I like about it is that it gets the texture of the carbonite perfectly except for the parts you have to fill in.
Most people screw the rubber in at parts even with adhesive. You will have to fill in just to hide those screw heads. The favorite is to use bondo.
Bondo is a two part filler. You mix it in... a little bit at a time because it dries quickly and work it in with a putty knife. Lowes actually sells little rubber bondo knives to work in the bondo. you want to use a little more than necessary and after it dries, you will go back and sand it down to look how you want it. I see you also "filled in" the Han area with plywood. I used sandalwood, which is a bit lighter, but you are doing it right. You want Han to be as level with the top of the box as possible. I see a lot of people give up on layering up and it looks weird to have Han recessed into the box. If the plywood doesn't do the trick, an extra layer of bondo ought to raise Han up just right.
Also, I see a lot of people putting holes into the plywood under Han and filling him with Great Stuff foam. This will add support, but it could end up bloating Han up, so it is a little risky if you don't know what you are doing. I have worked with Great Stuff and I love it, but it often expands unpredictably.
Good luck!