Re: Running 2000W coach A/C off the alternator.
The limiting factor here is probably not the alternator (some automotive electrical shops will rebuild alternators for higher capacity).
For example,
Instead, the expense and complication of purchasing and fitting the "fat wires" you need to make it work will be prohibitive.
You'll need two gauge 3/0 or one gauge 6/0 wires to carry the current. To picture this, you either need two wires the diameter
of your index finger, or one wire the diameter of your thumb. You will also have to run ground cables of similar diameter
between the inverter and the chassis, and between the chassis and the negative post of the battery.
I think the idea of mounting a 2000W generator on the bumper is probably simpler to implement.
Good luck,
Buzz L.
Phoenix, AZ
Former '86 Dolphin, '89 HiLux, and '96 Tacoma owner