Tested the fasted cardio and the lifting idea I threw around here....
Woke at 5:35, left house at 5:55. Got to the gym and started running around 6:10.
I did 20min on the treadmill at 6.0 MPH. Felt fine throughout.
I did a 2min cool down where I drank 1/2 of the shake below:
-35g gatorade powder
-5g BCAA powder
Then between the time I got off the treadmill, stretched, walked out to the tires and started smashing them with the sledge, it was about 20-25min.
Everything felt fine doing that and the rest of my training so I think I'll go at it again next week.