Leica Disto for Cabinetry

Our shop does custom built ins that require minute on-site measuring. Our leica disto tech records the room/alcove/etc and I generate the model for the room and design documentation for the project. Nothing is square, but we do need to know the smallest perpendicular L x W x H that structure could fit. The best method I’ve found to get that info out of a simple Disto file is to create a reference image with marked points in Layout, and then pull tape in the model on a locked axis to find and record the number. Tedious, but it is methodical and effective. Anyone have a better idea?