Sadly roping and sheeting is a dying art. (Well maybe not especially on a rainy day.)I would just tie it on with rope, especially if you know how to do it. Strap to the chassis is what they want to see though.
A policeman stopped me a month or so back, I had 4 pallets of bottles on my trailer which were sheeted and roped. He commented how I had done a good job of securing them and they weren't going anywhere. Also everything in the deck of my truck was roped too which also impressed him so he just fined me £50 for having the wrong number plate on the trailer.
I too have roped and sheeted many lorry loads of fruit, mine were going in to Manchester and Liverpool.