Thanks for the reply Jim but I don't think that is what they are for as they are large (4 in wide X 2 inch deep) whereas the hood bow mounts are normally round and smaller.
But on thinking about it and studying some pics I have in more detail you may be right. I have been thinking of something sliding into the cleats but they may well be spacers for hood bow clamps to attach to so that they clear the angled lip at the top of the tipper body.
so rather then clamps/cleats etc they are in fact spacers......hmmmmm
thanks again
Cheers
Cliff