Chuck,
You wont be able to take out either of the top two O2 sensors, as those are used by the computer for air/fuel trim. The lower O2s in the Y-Pipe, you might be able to take them out, but you will probably throw a CEL because the computer will think that O2 is not functioning/broken.
For the added ease of use, you may just want to spend the $25 to have another O2 port welded into your exhaust system after the Y-Pipe.
Nikolas
