Can I slip a box end wrench over the connector and slide the wrench down to the O2 sensor? If not what is the best way to take them out? Thanks in advance!!

 

Best way is to get a O2 sensor socket.

or

 

That really helps. Thanks!

 

The longer socket tends to flex and slip off the sensor and the rear sensor doesn’t have enough room to get the socket and a ratchet into position.
if you are changing the sensor then feel free to cut the wires off and slide a 6 point wrench over the sensor. Soak the sensor with PB Blaster and work the wrench to tighten and loosen the sensor until it starts moving and the unscrew it. Heat is you friend so remove both sensors before you start installing the new ones so you don’t damage them.