Hello all, very sorry for the what seems to be simple question. I was trying to install a new boss HU into my 90 z32. I was having audio issues and I’ve come to the conclusion that it is a piece that I have no clue what it is. I don’t know if stock or aftermarket due to the previous owner adding a ton of extra wires and making a mess. Any info would help. Thank you!

I have no idea, take a look at the wiring diagrams in the FSM (link in my signature)/ From the picture it looks like those are the OEM wires going to it, also I'm assuming you have the non-bose system. May be easier at this juncture for you to find a pigtail from a junc yard and xi your factory harness so you can use an aftermarket harness kit and have a clean install.

It was the Bose system... I haven’t been able to find anything in the FSM sadly. But thank you for the reply!