Hot Rods 8CM Breather Question

I bought a 1939 Ford project with an 8CM in it. It has an electric fuel pump. An oil breather/fill tube is in place of the original fuel pump, rear of engine. Is the original breather/oil fill tube, front of engine, needed or should it be blocked off? It looks like a 1 1/4" freeze plug would fit. The road draft tube was replaced with a PCV.

 

With the new breather at the rear and a pcv, the front oil fill/breather can be plugged.