I think the Williams was listed in the SCD Standard Catalog before Bob Lemke quit doing border gaps. By Gates Brown do you mean 508. On Williams and Brown the gaps are on both the left and right as is the case for many of the 73 gap issue cards
I do not have a gap for Sizemore, maybe Cliff does. I do have the two below. Note the cleaner version has a green streak in upper left just below white border
