Bosch O2 sensor connectors

[Navy911]

I recently bought an 84 3.2 ROW. It is my second 911 and I'm looking forward to "personalizing" it with mods. I'm replacing the CAT with a fabspeed Euro premuffler and have the new oxygen sensor (which wasn't connected on the original CAT. I've done my homework and been through the Bentley book and the forums here. My question is the Bosch O2 sensor I ordered from our host has 2 connectors one is a 2 pin that I can find the connection to in the engine compartment. The other connector is a single and has a rubber connector that I cannot find a match to. I read that one of the connectors is the O2 heater which may or may not be connected. Where would that connection be? Is it not there on a ROW? I'm stumped.