Both can be cut back severely and should recover well (no guarantees, of course). One of the public gardens in northern NJ known for its collection of rhodies cuts them back severely when needed. You may well lose a season, or a few, of blooms, and it may take a while for the shrubs to fill out, but the results will be worth it. Give them a gentle feeding of organic fertilizer and they should respond well.

Good advice. I would add that the time is now right before the spring growth starts. You'll have to do some occasional pruning in the future to keep their size in check. If you don't want to do that then you should consider replacing them with a smaller cultivar.