Quick project.  Bought a momentary press 19mm button from amazon, removed the pins I didn't need (only left common and normally open) and wired it to a cheap garage door remote.
Switch:
Untitled by Uncle Grr!, on Flickr
Wires soldered to button pads
Untitled by Uncle Grr!, on Flickr
Tessa tape applied, hot glue added as a strain releif
Untitled by Uncle Grr!, on Flickr
Remote velcro'd to the tank behind the oil dipstick.
Untitled by Uncle Grr!, on Flickr
				
			Switch:
Untitled by Uncle Grr!, on FlickrWires soldered to button pads
Untitled by Uncle Grr!, on FlickrTessa tape applied, hot glue added as a strain releif
Untitled by Uncle Grr!, on FlickrRemote velcro'd to the tank behind the oil dipstick.
Untitled by Uncle Grr!, on Flickr