They may have a different engine code meaning it may be a Duratec of earlier version versus the Sigma motor Fiesta uses in the US.
So the Hex head you're looking for has been superseded by a self-tapping coarse thread bolt they also use for the US version of the Throttle Body to the Intake Manifold bolts.
The concern comes from the LENGTH the bolt needs to be - so if you can find a local source of similar thread bolts, we'd like to know the size and length you acquired in mm to help the rest of us.
One type is the older type and is a simple Hex-head bolt while another, which is the newer, is a coarse threaded M5 Hex SOCKET head type which needs a Torx wrench versus a socket wrench.
In the above YT shot the older HEX bolts are seized and so the plastic broke off from the case.
YT link here...
This was all done due to issues of seizing of the bolt to the cylinder head flange that stuck out the side of the cylinder head for mounting and tapped to fit those bolts, sometimes they can be reused but due to the dissimilar metal galvanic corrosion issue, they came up with a plated and coated bolts to replace them.
Product Specifications
Brand Genuine Ford
Base No. 56903
Manufacturer Part Number CM5Z-00813-B
Part Description Screw
Other Names Ignition Coil Screw
Manufacturer Note
M5 x 25MM
Item Weight 0.50 Pounds
Condition New
Fitment Type Direct Replacement
Replaces CM5Z-813-B
Require Quantity 4
Manufacturer Ford
SKU CM5Z-00813-B
As far as I can tell, the new bolts are to replace the older fitted by thread and pitch - bolts from the OEM.
Note the replacement bolt is coarse thread but it's shank is designed to fit the hole the finer pitch threaded bolts they replaced, used.
