Ah.
On the hitches to go website... The only PDF I could open on my computer was (is?) the PDF for installation on 1987 - 1995 Pathfinder. (PDF 36152) which does not indicate drilling holes is necessary. Although it does note a 1/2" drill bit..?
(don't know why I couldn't get "Pickup truck" [PDF 75186] instructons to open)
So I presumed (evidently incorrectly) that the install would be the same for my 1993 pickup.
My bad.
I had saved those links from many months ago when I was considering putting a hitch on my truck but I am sticking with the step bumper/hitch.