mrtag

So I got this 1995 G20 van, explorer conversion I believe, that I fully gutted and got ready for a camper build. I did remove miles of original conversion wiring including the speakers and an old audio system that was installed in the van area(behind the driver seat under the window ) The other audio unit, inside the dash, was already replaced by the previous owner with a newer model. Now the problem: all the speakers were connected to the old audio unit. Given I got rid of that unit how do I connect the speakers to the dash newer unit? The dash audio has all the wiring connected to it but I can’t see where does this wiring go. There are no wires that would go from the old audio unit to the new one unless I missed something. Any help will be very appreciated! Thanks!