Same problem here. Everything went great except the antenna grate. I spent more time trying to get it back in place then it took to do the complete dissasembly reassembly. The key is not to force it. The top edges of the grate have to fit in the grooved edge of the housing. I used a paper clip and bent one end into a small hook which helped to align it up. I'm not sure what I did but it finally popped into place and the screws magically aligned. Elation!
I have a set of dental picks that I use for circuit board repair. They came in handy (like you) on the antenna grate, and when I removed the IR board cable.
In the directions they show removing the IR board cable by putting the plastic sponger under the wires but there was no way that sponger that OWC gave us was going to fit under those wires... thus I broke out the dental picks. The paper clip would also work there in a pinch.