Import USA sales contract ?????

Dear community, have a question about a US import of a 74 el caminos. And that’s about the thing about the purchase contract. The vehicle is to be picked up by Interfracht in El Paso TX directly from the seller. This should give him the original title and the original purchase contract there. Since some of you have already celebrated this several times I would like to know how you did this with the purchase contract. Did you fill out the here blanko and send it there? Lisch, or both ? The vehicle is an ebay purchase. Does the customs authorities not even have the expression of the surcharge ? I would be grateful for a quick answer. The vehicle is already paid (paypal) and since a week there and waits for collection 😉 Another thing: Should I really let cat litter in the car for shipping in the container ?? ( Tip of Interfracht . . . ) And what about frost protection if the vehicle is launched in Rotterdam in December Thank you for your efforts, Jens.