I made a template by scribing two adjoining squares on a piece of MDF, using compass and straightedge, then marking each corner with a centerpunch, then drilling the points with a 1/16" bit. I find I'm always breaking small bits, so I picked up a couple of each size some months ago, and on looking I found I had three 1/16" bits, which worked fine for what I intended.
2 - use a plunge router with a bottom bearing cuter bit such as this from rockler: http://www.rockler.com/product.cfm?page=25160&site=ROCKLER .... I thought to use the short one as I plunge it directly downward in the centre of the hole until the bearing reaches within the tabletop hole. I suppose one could use a long one, but the stubbiness seemed more practical (the big bearing ensured accuracy?)
Grizzly is a company currently undergoing an upheaval. This brand was once known as a manufacturer of professional grade tools and equipment for woodworking products. Though, in recent years, that reputation has begun to slip a bit since being bought by the Chinese company SIEG. These days, whether the Grizzly product stands up to its previous standards of excellence often has more to do with what you are buying than the company itself.