I also mounted the motor mounts to the mounting tees, and gave the motors a test fit. The blades seem to have a good amount of clearence between one another, and the spacing seems quite good too, gotta love trigonometry.
Here is a closeup of the motor mount:
The zip ties hold it in place quite securely. In this picture I have yet to clip the excess from the tie, but that shall happen. Three ties hold each motor in place.
That's all the progress to date, stay tuned for more at some point.