3/4" would be about right for bench dog holes. Did the bracket stick beneath the table any appreciable amount?
http://www.mprime.com/Emmert/anatomy.htm
Go down to "tilt adjustment mechanism" Was it mounted like that?
Was thinking maybe due to position it might be the tilt rod bracket for a pattern maker's vise... like this one:
http://www.ebay.com/itm/Emmert-Vise-bench-bracket-assembly-/370290461827?pt=LH_DefaultDomain_0&hash=item5637080c83
I just got the Phillips set myself. I was planning on buying the set you have later on, anything you're looking for? Perhaps we can do a partial trade/cash deal or something. I have no idea what I'm going to use the #4 Phillips for but it's a nice set.