I'm a rank amateur on this subject but I've had guns put back on face using both methods. Regardless of which method is used the hook still needs to be refit to the pin by filing.
You have had it done both ways.....?
If you had someone put in a new hinge pin, there is no need to file the worn barrel hook UNLESS you want more slop...........because the gun will still be loose...... you must first weld the barrel hook requiring the new fit......since most competent smiths laser or tig weld the hook, the hinge pin is left as it is..........therefore replacing the hinge pin would be a waste of time..............
Cheers,
