Well eventually plumbed in my zetec no longer pushing coolant out the header . She's plumbed in like the mondeo with bypass going into top hose. Have now had no issues with the expansion tank, coolant level is about half to quarter. She seems to warm up normally but after a good blast ths temp gauge on the dash sits at 100- 105 even with the fan going and when stationary doesn't seem to drop much. The fan currenty is hard wired on as I have yet to get a temp switch for it. Just wondering if this is too hit for normal running or if this is correct looks from other write ups should sit at 90 ish . Temp gauge is taken from the thermostat housing in the engine but under the bonnet is very hot after a run but suppose it would be as it's pretty tight in there. Any inputs would be appreciated.

sounds like you have a 100c thermostat

Strange as it may seem the temperature gauge on modern tintops is driven by the ECU and will remain on "N" between about 70c and 118c

This is the graph of a Rover Gauge

Its essential that the sender and gauge match. If you still have the original Ford sensor and are using an aftermarket gauge the reading will be completely wrong, been there, seen that. VDO gauge, Lucas sensor, 110 C at 78 C.

The standard bypass on the zetec goes from the stat housing to the bottom spider hose via a metal tube that passes over the exhaust mani then drops down.

NOT the top hose.

glad to see you back up and running,mine left running tends to sit at about 90 and brings the fan on @ about 100 this is using correct gauge & sender