Jim, lets get the basics out of the way, black is hot, green is ground, and white is neutral. You have a decent looking set up by the way. Here is what I want you to do.
1. Disconnect all shore power, inverter, etc. make sure the system is completely dead.
2. Put it back like it was originally so we start clean.
*SPECIAL NOTE* The next two steps are assuming the main feed from the shore cords are going to the left hand side of the main breakers, if they are going to the right hand side, switch the next step to left instead of right. It appears from your pictures that all 3 go through the breaker. If they do not, just locate where the green and white wires connect to the buss and disconnect them from the buss.
3. Circuit 2, main breaker 2, right hand side, follow the white wire to the neutral bus, disconnect it from the neutral bus. Using a meter, check for resistance from this white wire, to the white wire coming from your other shore cord (shore power 1) there should not be any, there should not be any connection between the neutrals now. If there is, stop now and post.
4. Circuit 2, main breaker 2, right hand side, follow the green wire to the ground bus, disconnect it from the ground bus. Using a meter, do the same test above with the grounds. Needs to have the same result, But if the ground does show connection, continue on with the next steps but post that. It may be grounded at the breaker.
5. Your hot's do not share a common buss, it is split, look in picture 4 from the top, go to the bottom left hand side where the black wire connects, move up from there and you will see where the metal stops and there is a space there. That is the split between the circuits.
6. Right hand side of breakers ac1, ac2, and ac water pump. Follow those black wires until you determine which 3 cords they go to. It looks like everything goes to the bottom right hand side of the panel. You might have to do some pulling and tugging there to get this done. You should end up identifying 3 cords, ac1, ac2, and the ac water pump.
7. Once you have the 3 identified, follow the white wires to the neutral buss, disconnect them from the neutral buss. Wire nut those to the white wire from step 3, you will end up with 4 white wires tied together, they are ac1, ac2, water pump, and the shore supply neutrals.
8. Repeat step 7 for the green wires, wire nut to the green from step 4. You will end up with 4 green wires tied together, same as step 7.
9. Double check each step and double trace the wires to make sure you have the right ones. This will not work if you pull the wrong ground or neutral.
10. Test. Do this step just like I am saying, unplug shore power 1 from pedestal. Only have shore 2, connected. Test your ac units. If everything works, great, if it does not, you have the wrong neutral, if the gfci trips, you have the wrong ground. Once good, disconnect shore 2 from pedestal, plug in shore 1, test shore 1 power, if everything works, great, if not, you still have the wrong neutral, if gfci trips, you have the wrong ground.
11. Once 11 is complete, try it all, both cords connected, then turn it all on and see what happens.
If all this works, and there isn't something I am missing, you are effectively isolating the two circuits from each other. If it still trips the gfci, and it might, then we need to look at the main breakers in your panel. I suspect however, doing the above will solve all your issues..........D..........
