Lazyman commented about 2 hours ago new Any easy solution. Is there a reason you cannot drill the counterbore first and use the Forstner bit's center for the location to drill the 1/4" hole?
That would be ideal, but the bolt hole goes through a floating tenon of a mortise that is cut on the inside, so there's bound to be a little bit of variability in both the mortise location and the position of the hole in the tenon. I know generally where the outer counterbore will be, but not precisely. If I drilled it first, I'd likely be off-center once the bolt hole was drilled.
