I may wait until October when the cooler weather arrives, after all,l it's been that way for better than 5 years a couple of months should make little difference. A 60' trench is gonna take some work with a pick and shovel. A shove and pickle.
The situation with the drains is much worse than I thought, the main sewer drains were also damaged during the quake and subsequent aftershocks of five years ago, a real live DIY job to get my teeth into.
I don't use painkillers, as a rule, the trick is to know your body's limits and when to call it a day.
Work as ergonomically as possible, if you're small use a small shovel and so on. Even a mountain can be leveled one chip at a time.
I hope that it all goes quickly for you. My brother dug his out by hand and replaced the pipe in one day, but waiting on the inspector took a lot longer than that and he had to build fencing around the ditch that he'd dug to keep pets and people from falling into it as it ended right next to the sidewalk. He had to retrieve his dogs many times over the week or so that he waited for the inspector.