For those interested, the generic Kat's 35mm freeze plug heater does not fit the Ford Zetec.
I was soo close, I had to bend the heating element up quite a bit to get it around the narrow opening in the water jacket, but when it came time to tighten it up the bolt snaped
because it is made for a deeper water jacket. Oh well, I did get the oil pan and trans pan heaters hooked up. They are hot to the touch in less than a minute.