Scott US 26A Type IV Question

In id'ing some stamps I found a washington 3 cent That I believe is a type four it fits all the characteristics for a type IV. Scott specialized says that many type III top or bottom of the plates are mistaken for IV's. My question is would a type III top of plate or bottom have perfs all around or would the top or bottom be flat. I would post an image but didn't buy a scanner yet and can't quite get the detail with my camera. Thanks for the help.

The 25/26 were printed in sheets of 200 consisting of 2 panes of 100 each. the panes were cut vertically with a straight edge. The top. bottom and one side had perforated margins. See right pane example below.

Thanks for the picture Russ. Is there any other obvious ways to tell the difference,without getting into plating, between a type III top of pane and a Type IV. I'd Hate to have to buy a new reference for an issue that I only have about ten stamps of. Then again it could give me a reason to buy more! LOL

The outer framelines on the Type III are continuous from top to bottom of the pane and the Type IV the outer frameline is the height of the design and is broken at the top and bottom. The top row of Type III will have the outer frameline terminate at the top of the design (top of pane) but the bottom will still show the continuous frameline if there is enough of the design to see it. The bottom row of Type III will have the outer frameline terminate at the bottom of the design (bottom of pane) but the top will still show the continuous frameline if there is enough of the design to see it. If it cannot be determined that the frameline is continuous then it is assumed to be a Type IV unless plating can prove otherwise.