1995 4l60e transmission problem

I bought this 1995 blazer s10 w/o the trany. I picked up a trany and installed it, but there seems to be one extra electrical connection on the passenger side. Is it possible I got the wrong year? Branching off the harness on the pass. side is this small connector (not the big round one) with a short run off wires. Does anyone know where this goes?

does it go to the O2 senser just ahead of the cat
 

yes it does!!!! Thanks for the reply. The cat is out and I thought I was screwed.

Hey no prob anytime good luck