The essence of pushing is giving up shadow detail in exchange for speed.
I'd give up as little exposure as possible.
If you have a fast 50mm lens use it, I'm assuming 35mm film.
Get on stage before the event and incident meter in the actual lighting.
If you need and can, use a strobe.
Shoot a couple extra rolls while you are there to test development with, develop the test rolls first, one at a time. Adjust as required.