Wiring into accessory plug in backof Stock Delphi head unit?

[kayakingsteve]

After some mis-steps I have gotten my aftermarket head unit wired up to the stock amplifier on my 06 Vibe, and it works...

Now I am noticing that there is an "accessory" plug on the back that on some wiring diagrams lists a right and left aux in... All I wanted the aftermarket HU for was an aux input, but could I have just spliced an RCA jack into the two aux wires on the accessory plug? Anyone done this?