I experimented just a bit but couldn't figure out how to turn off both the extension lines and the leaders on a Basic angle dimension. There might be a way I don't know about.
You could easily create a Sketched Symbol for reuse in labeling the angles. By using a Sketched Symbol you can have the Basic rectangle around the text. I am using r2008 otherwise I would post an example.
On a side note it appears on quick inspection that those NPTs are at regular interval angles. I think I would have done one then circular pattern and suppress the unwanted instances rather than create a bunch of workplanes.
BTW - if you had pulled up the EOP marker before zipping to post the file would have been much much smaller file (I'm on a very slow DUN connection).
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