Can you tell us which config you got, also how many ports do you need?
One of the issues you face is the limits of PCIe lanes. While you can bridge additional lanes off of the core lanes you can get into lane contention issues! So you can loose performance if you are not careful!
How about making a drawing on what you want. Nothing fancy just block off each TB device and what it is. on the left column and then on the right what your system has in each slot now. [guide|21499]