How to: Pack Vinyl Collection for Shipment on Boat

Moving to Europe this week and need to know how to properly pack a record collection of about 200 plates for shipment. I have the packed in Scorpio record shipping boxes that I sourced from a local shop, they are cardboard with padding. I am concerned about the heat and moisture as they will be sitting in a storage container as they travel across the Atlantic for 3 weeks in the heat, baking on the deck.

1: Wrap cardboard boxes in plastic?
2: Store vertically of lay them flat, to avoid warping ?
3: Moisture control?
4: Please give me any advice to help me ensure that they arrive in the condition they have left.

 THanks guys. I will be looking forward to your advice.
Don't do it! Double box them, then arrange to have them shipped by air in Winter. If they sit on the deck of a boat for three weeks in Summer, they WILL be warped, very possibly no longer playable.
In three weeks they turn into one big vinyl mass from 200. The best way is to take them with you on the plain and pay extra luggage expense.
200 records isn't a big collection. You can also arrange air-freight on cargo airline of your choice to receive your package from destination airport in person.
Winter or Summer doesn't matter for air-cargo transportation.