[Hoff]

I'm reading through the shapes threads, and would love it if someone wiser than I could tell me if what I'm trying to do is possible before I study too much longer.

I'd like to make arrowheads with + and - symbols inside them. It could be a filled triangle with white symbol, or unfilled with black. I just need this one symbol at the end of a connector, and would like to do away with fiddling with the line labels.

Thanks for any insight!