We don't recommend using an in tank pump for any escort cosworth that is driven hard as even a standard car will experience fuel surge with anything under half a tank.
Allthough the Bosch 023 is a decent pump, the tank itself is terrible and thus you need to go to an external swirl pot, Bosch 044 external pump, and use the intank Bosch 023 as a lift pump only to fill the external swirl pot.
If you need any help we can supply you a full kit that mounts under the car.