Hi Brent,
the Autovac listed for sale should work but it is not quite the same as would have been fitted to your Wireless-Ant, the top is different in that the vent had a brass, bell-shaped cover. It does have the mounting brackets as well, which you may need.
The Autovac is a simple device, it is a double-chambered cylinder, with a float in the upper chamber, more on the float later. The vacuum from the manifold connects to one of the top elbows, the other elbow marked "IN" is the petrol line from the tank selector and filter. There is a shut-off tap at the bottom of the Autovac, which feeds the carburettor, this must be turned off when the engine is shut down. Feed to the carburettor is by gravity.
Petrol is drawn into the Autovac and enters the top chamber where it passes though a non-return flap into the lower chamber, then feeds out through the tap. When the lower chamber has filled, the upper chamber starts filling-up, as it does the float rises and begins to open the vent thereby reducing the vacuum until no fuel is being drawn in. As the fuel is drawn down the float lowers and shuts the vent and again fuel is drawn into the top chamber.
There is also a drain bung in the base of the Autovac this is for cleaning out condensation and etc. this must be done periodically else it will rust through.
There are a couple of ways to prime the Autovac should it run dry:
1. By the manual - shut off the tap at the bottom of the Autovac, remove the the carburettor bowl fill it manually, replace and start the engine. Repeat until fuel is evident in the lower chamber.
2. My method - shut off the tap at the bottom of the Autovac. Undo the "IN" pipe and move it slightly to the side, using a short section of rubber hose that will slip over the elbow, feed in petrol. I always carried spare petrol in a reserve tin, a rubber tube and a small pourer.
3. Tow start with the fuel shut-off tap open.
Hope this explains sufficiently how the autovac works.
Cheers,
Dave