Any recovery tips for after I cross the finish line?
I tried to keep moving as much as possible. Change of clothes (socks, shirt, etc) to have something dry to wear. Depending on finishing weather, long sleeves or a coat/jacket to put on as well (I was freezing at the end of Philly. Stupid 35mph wind).
I walked the mile back to my hotel, stretched / foam rolled, tried to eat something (leftover bagel), took a shower, and then proceeded to drive 3 hours back to my house. Getting out of the car at a rest stop about 2 hours in was a slow, painful process. I could best be described as hobbling. Got to the house and ate what seemed like half the menu of the local pizza place.
I did do some short, slow runs later in the week and went to the gym to do some light mobility and stretching stuff.
For comparison sake I ran a 4:14. Held a ~9 min pace through mile 19 and hit the wall badly. I probably only ran around a third of the miles I needed to in the last 6-8 weeks of my training program due to injury. I had been running a 1:45 half at the time.
Enjoy the run. I swore I'd never do a second one but about 6 months later I was looking for a second one.