I would suggest getting them done at the same time. They will be quiet together and this will make it easier on you.
Hot Rod was out of it for about 3 days...he also had teeth taken out. He was pretty quiet and then still was not 100 percent but much better. Chances are that they will sleep the first night of being neutered so if you can schedule it on a Friday, then that would be good. Or even if it were a Thursday cause they will probably be quiet on Friday also.
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feel free to pm with any questions. Good luck and let us know how they do.