While trying to cut the sanding drum opening in the top on my table saw and then use a handsaw to complete the cuts I realized that there had to be a better method to do this. I turned to my Bosch Pony trim router. Yes, it was a better way :-)
Here you can see the fence that I clamped in place for the router and the first cut made with a 1/4" straight bit. It did not reach through the top and left a bit of a ledge - not a problem as this was taken care of easily when the top was turned upside down. This is the topside of the top. This bit was part of a 3-bit set of a Bosch Laminate Trim Set, #RBS020XW, 1/4/" shanks. All 3 bits in this set were used in making the top. It's a good buy if you don't have these router bits.