why dont you fix the timing belt size engine mount too at this time. remove mount, take a drill with hole driver and drill 2 holes in the chassis leg to accomodate the 100 series mount put a tube in them and a couple of long bolts tightened with nuts underneath.
OR, drill through the original spot welds and move the whole mounting ears to a new spot on the chassis leg and reweld it back.
OR, make an adapter plate with the mounting ears and drill horizontally in the chassis leg and tighten with appropriate pipe inserts, nuts and bolts.