All you need is a Dremel or some sort of way to cut it in half cleanly, ABS cement, and sand paper. You should also source a ruler that is made for right angles to ensure that you make a cut that's perfectly perpendicular to the lip.
And your lip is made of ABS plastic, not polyurethane. That's why it has a crack in it. So yes, ABS cement will work on it just fine. Technically this lip is closer to PVC which is why it's hard and brittle. I've done it to my front lip once and this lip, ABS cement works fine. It sets in a couple of minutes but you should let it dry overnight. It's really easy to do and it is strong if used on ABS.
You can get the cement at any hardware store like Home Depot or Lowes for like two bucks or three bucks a can (you don't need a big can), but yes I have pretty much all the materials except the sand paper.