If the standard engine mounts are in good condition with no visual damage, and the rubber insulators are not broken or sagged (ie the threaded rods on each side of the insulator should be in line, not offset) the engine should sit squarely. The flat Vee on both sides of the crossmember cradle permits slight rotational alignment if needed prior tightning to set into the correct position (hence the long slots).
On right hand drive Escorts Ford did apply fudge factor by offsetting the engine to the left side of the car. The left hand side and right hand side mounts (the brackets that bolt to the engine block) are not of equal length. The longer bracket should be on the drivers side of the engine block.
The main thing to look for is a clearance of several millimetres between the bellhousing and the floor pan at the firewall and approx 10 to 15 mm between the sump pan and the engine crossmember.