You should have (1) T in the rear of the manifold and (1) in the front which is is pictured below.
Since there is no vacuum port on the front of the M370 manifold, the "T" connection in the rear provides a port to connct a hose to run to the front of the manifold. The second "T" connection is used in the front to connect the hoses at the front going to each valve cover for PCV (positive crankcase ventilation). Other than that, the other connections are the same as the stock manifold. The instruction sheets are correct.
If you have 2 T's in the front, there is somer sort of redundancy that can and should be removed for simplicity. Try drawing it out on paper and make sure it make sense.