I see from googling that the Heatrae Gold Dot product in 27" size still exists. Can I buy one, safe in the knowledge that the thread will be the same? (In other words, I won't get a nasty surprise when I've drained the hot water & unscrewed the old element, & am about to try putting the one in. I'd really prefer not to have to leave everything hanging open while I cart the old element to a shop for comparison.)
Also, are there any tricks for getting the water level in the cylinder below the fitting for the element? Or do I just shut off the water to the cistern, run as much water out of the hot system as I can, and then mop up what runs out when I unscrew the old element?