Don't do it. I had one put one in my 2012 Mazda3 I touring and regret getting it done. It rattles and squeaks. You can hear the wind noise. The place that did it sucks too. Had to go back twice because first time was rattling, screws fell out and had to be tightened. Second time was a rubbing noise, wires not tied correctly. First and last time I get an aftermarket sunroof. Should have paid extra and get the factory one and leveled up on trim level. Also it looks cheap and and only opens half way.
Webasto has bigger than oem sunroof if I'm not mistaken, and I think I saw a honda fit or the scion on google image search with the exact sunroof your just described. Then I read it was discontinued..I'd worry about the amount of roof supports that would be cut in order for that to work..no one wants roof sag.