"Jim Wilkins" wrote in message
news
.....
I found it easier to locate and drill the first hole, hold its disk
in position with a dowel pin, put the second disk on a chucked dowel
pin and move the table until the disks touch.

These are stiffer and don't damage a drill jig hole in mild steel as
quickly as longer-fluted bits:
http://www.travers.com/spotting-drills/c/297807/