OOPS! Its there to give an even distribution of load when the new bolts are torqued down, and also stiffens up the Pressure Plate to cope with repeated operation,
Short term, probably be OK. Long term, I'd expect the Pressure Plate to crack with metal fatigue around the holes, but exactly when is an impossible question to answer.
Unless you're thinking about taking the box out anytime soon, you may as well leave as is, because if and when this fails, you'll be needing the replace the clutch anyway!
Thom