Escort and Mondeo Zetecs have completely different sumps. Bonzo had to cut out only about 2 cm out of his Escort sump. Mondeo sump has a sloping bottom and has to loose some 5 cm at the deepest point.
The datum you're looking for is probably the distance between the center of input shaft and bottom of bell housing on the Type 9 box. It's 155 mm. The bottom of the bell housing dictates the depth of the sump chop. Also, the book prescribes positioning the engine by putting it on the floor and raising the chassis on pieces of 25x25 scrap. So, the design height of the crankshaft is 130 mm from the bottom.
Here's how I positioned my Zetec:
http://fridge.pov.lt/~alga/zetec/chassis.dxf