You might want to set up a small bore gauge and check all the lifter holes while in the engine next time. There IS a spec limit on the diameter; I suspect very few folks check this.
I did some basic checking during assembly and pre-lubing, but, lacking a proper bore-gauge at the time AND having no means of correcting any issues here, I didn't spent too much time on it.
I can probably loan the bore-gauge for the next time the engine will be opened up, which will be when the aluminium heads will be installed.