Welcome to the forum, Here is some info for you, hope it helps more than it confuses...lol Way to late to be up typing...
There are many ways to wire in a gen-set. If the unit is to be mounted on the coach, then connecting through a transfer switch (either manual or automatic) is a requirement if you are going to also have shore power. You want to make sure that there is no way to be powered from two different sources of electricity at the same time (nasty things can happen if power is back fed from one system to the other). If you plan on using a portable generator,then the easiest way would be just to plug your shore power cord directly into the generator outlet, this creates the simplest and most reliable of transfer switches as you can not physically plug into two places at once. Check your generators paperwork, some can be wired to output to two 120v circuits or one 240 volt, some come already wired for both. when you plug into a 120v outlet on the generator you typically only get one half of the Kw rating. as the rating is usually phase to phase(240) not phase to neutral(120). To use the full capacity you would need to run two cables to the coach, and use two separate elec panels to split the load, a 6.5kw will probably have a 25 or 30 (6,000 to 7,200 watts) amp breaker on the 240volt outlet, and each of the 120v will only have a 15 or 20 amp (1,800 to 2,400 watts) breaker
The big thing with a portable unit is to make sure it will handle the load you plan to run at one time. Some of the units are rated at peak power not at continuous running load. Some of the import units can actually only handle a portion of their listed capacity. There are a number of adapters available to allow you to plug a 30 or 50 amp RV shore power cord into a smaller outlet which will allow you to power the coach from a smaller generator as long as you are mindful of how much you turn on at a time. All modern portable generators should have a built in circuit breaker that will trip before damaging the unit. However you will need to go outside to reset it, and to add fuel. You will learn quickly which combination of loads trips the breaker.
Unless you are running AC units (and microwaves) most of the loads in an RV are usually fairly small, especially if you heat with gas.
for the more scientific method you can pick up a watt meter from the local hardware store (Kill-a-watt is the common one), then plug it into an outlet, and plug in your appliances and it will tell you exactly how many watts ea one uses in operation, you will find many items use quite a bit less than what the label or paper work state. The meter will only handle 15 amps (1800 watts) but if you test things one at a time it gets the job done. don't forget to plug the shore power cord into it and measure the built in lights as well. Once you have all this data, you can make some good judgments on what size generator and inverter will work best.
Inverters are great, especially when you are camped in a state park with no shore power and unable to run a generator at night. you can power laptops, tv's or even the microwave for a quick back of popcorn. Some of the models will even provide load management shutting down loads as battery power drops.
my .02
Dave