The first thing I would do is root-prune them and let them redevelop new roots at the cut for awhile before moving them. This means that you use a sharp-edged shovel or spade and make a deep circle all around the bush, severing the longer reaching roots, about at the outer drip line. I don't know whether pruning the branches before or after is the answer, though. I would think that pruning before would stimulate new growth and that might not be what you want before the bush is re-established and well-rooted elsewhere. Ideally this should have been done sooner since moving a plant when it gets hot is risky.