[Cunningr]

Did the amp wires get chopped up in the frunk too? I am with Tony on this spend a little money do it right and be done with it. The previous owner was probably using a 5 channel amp power sub, door, and 2 dash, with the tweeters powered from the head unit. The sing rca maybe for sub out channel or a back up camera.

Easiest if there is such put in a double din hu, use it to power coaxial speakers in the dash wings to get all channels working nothing will be easy as its tight under the dash

There are several good sources for parts and and such like parts express. The door drivers are 5.25” if I remember correctly. Dash wings watch the depth, but you can squeeze 4” speakers. Or you could buy separate components. Many options.