Please help a stressed guy out, pics of which primary o2 connecters on firewall

[speedtrapped]

Need to also do the easiest check, rverse the connectors for the primary o2's, there are 4 in a group, does someone have a pic, or verbally guide me? Please....

[kismetcapitan]

Z19, Z28, Z29, Z30? I'm also curious...where in the exhaust did they stick those??

[speedtrapped]

Closest to turbo, and they are large black 4 prong I swap tonight, however my kid messed with my computer and I am locked out! No vAG tonight