I have heard that it is really easy to overheat this compound, so bring water sprayers. I don't have personal experience, but that is what some fellow autox'rs have told me.
I would go wider:D
Parking Lot Hero
2008 WRX daily driver
2003 ZX3 23D Autox Car 42 FSP
"Hella Functional - Raced, Not Hard Parked"