Since it's time to over-drill, epoxy fill, and redrill all the holes, the new clutches can have slightly different holes by 3/8 or so and the new clutch base will cover it all.
When our OEM clutches were wearing out, I replaced them with the heavy duty D2 models from Lewmar. They work very well and hold our very-low-stretch (T-900) 5/16 halyards.
You might want to consider this upgrade...