If you have multiple boxes with the same HIN and one or two are too big load the small ones in HIN order, drop the big ones to the floor, and mark the ones on the shelf with a down arrow. Mark the top and/or side of the floor one(s) with the HIN number if the label isn't visible. This is assuming you using a marker instead of ripping labels.
I can't even get my loader to load hazmats on the floor, he thinks I'm crazy and started loading orm-d's to the floor and keeps putting hazmats on the shelf and only pulling papers roughly 50% of the time. I've tried explaining multiple times but I just check the entire truck before leaving now.