Kenworth t680 No radio

My truck did not come with a radio so we are installing an after market radio.
There are speaker wires behind the door grills, but no speakers. We have installed a jvc radio and speakers in the door, but we don’t have connection between the radio plug in the dash and the speakers in the door.
Am I missing something?
Does it go through the fuse panel for some reason?
Or is there another plug we have to connect to get the speakers going?
Where do the speaker wires behind the door panel terminate?
The radio powrs up with the existing radio plug behind the dash, but nothing to the speakers.
Anyone out there have any experience with this?
Thanks
Ken