The only way to do this is going to be to drop the center dome. All of the wires run up the walls to the center dome. Then they run along side the right or left spar in the roof. The wires are grommeted and also bundled with clips and duct tape. Pulling a new on through using the old oner is in most cases a futile effort. Once you have the center dome out you can pull the wires through to the center panel from the individual speakers.
WBCCI #5501 AIR # 49
1978 Argosy 28 foot Motorhome
Wise men talk because they have something to say; fools, because they have to say something. -- Plato