Sony HeadUnit has two sets of Pre-outs? What Do?

The preouts are labeled "front"(1) and "rear/sub"(2). I want to connect a equalizer which only has one set of inputs. The Eq as three sets of outputs "rear"(1) "front"(2) and "sub"(3). Two amplifiers will be running off the Eq, a 4channel amp connected two both "rear" and "front" respectively And a Mono amp connected from the "sub." The Question is in which output from the HeadUnit Do I connect the Eq? "front" or "rear/sub"? I need the full signal.