ok a few idea's, 1st is it absolutely certain that its the front making the noise

?

I ask since, it is very easy when lowering the rear

- for the control arms to hit the bottom of the sub frame which would cause a clunking noise.

If its definatley the front

- then a bit long winded this method

, but it may provide the answer for you:

Disconnect the arb both sides, remove one strut, make a note of the height settings, remove the spring, refit the strut to the car without the spring.

Obviously it wont be driven but you can then manually take the suspension through its full travel

( with a jack

) and see where your suspension is fouling/clunking.

edit, just to add

- on these coilovers are they identical passenger/driver side

? If so, could swap them over to see if the noise transfers.
