i downloaded a i phone 4 3d file from a site named 3d contend central. de developer of te file claims to create cases whit the file. you could subtract the iphone shape from a sollid. or you can do an interferance chek. i have the sollidworks file attacht to the link. don't know if it is the richt year. if you want the file in a other file type than visit 3dcontent central.
Is that a Solid-works file. I do not know that file extension as I have AutoCAD and Max background.
As for the Apple drawings I think the moot on other forums is correct. The dimension is inferred in Detail B (looking at iphone 4s), as from the center of the rear camera. So we get a dim of 8.77mm. If you have an iPhone handy draw or print it out cut it out of paper and offer it up to the real fillet, if it fits wear it.
Just added this if anyone else is gonna do it from scratch.