Hi,
I think the best thing to do is find the original black, washer pump wire, then determine which bracket goes on which side of the engine bay (there were three as far as I know):
The "cage" bracket (wraps around a very hard-to-find square bottle) was usually fitted to the right side of the bay in front of the carbs on the early cars (thru '66), you'll probably find the black wire tucked back into the harness with the THICK black generator wire and the red amp-light wire. If these are the only two wires on that side, that far forward, it was probably snipped at some time.
The were two flat brackets for '67-on: one (very flat) bracket that nestled the botle between the remote brake booster and the master cylinder, and one (with a ridge on the lower edge) that located the bottle forward of the brake booster. The one with the ridge sits -kind of- on top of the ridge on the foward portion of the inner fender (hard to explain). You should be able to find an un-used black wire somewhere in that area. To test the "found" original black wire, hook a test light to it and pull the wiper switch out to the third position.
Best,
Shayne.