Actual Wiring location

[DadRich]

I have a 2010 28 BHS with enclosed underbelly. I would like to add a USB charger as well as wiring for a future possible inverter near the TV over the dinette.
I have removed the Jensen DVD player and the power wires are looped with the power to the DVD player coming from a quick tap/ clamp on connector attached to a loop pulled from the wiring chase from inside the wall.
How many quick taps can a person use without affecting the performance of the wiring?
Does anyone know the actual route of the wires back to the power distribution box/converter?
Is it easier to go down through the underbelly (removing the panels) than trying to fish it through the ceiling?
Assuming that I would put in a 400w inverter and only run the 50W t.v. would i need to upgrade the wiring? (~4.2 amps @12v = 50 W).
I apologize for not knowing the actual wire size, the trailer is 2.5 hours away, and I get these great ideas on Monday.

Thanks
Rich

[wabirch]

Even a 12v schematic wont give a precise path, start there maybe. Shoot Jayco cust serv a contact form and good luck