Tweaks for a Gallo Nucleus Reference II

I have a couple of Gallo Solos and another one of References. When I bought the References, I was given a second pair of CDTs, that were supposed to be extended frequency (going down to 1khz instead of 2,5khz).

When one of the original tweeters failed, I decided to open it and repair it (it took me ages to buy the rivets, and I had to buy 500!). The originals were far too brigth (as are my Solos - I drove all of them with Mapleshade DoubleHelix and a MF KW500). When opened they had a couple of infinicaps measuring 5,75 uF. I changed the tweeters and found that an acceptable balance could be had only with 4 uF Dynamicaps(different trials with the original tweeters show that the right value for them is around 5,40 uF).

However, they sound right only at low to moderate volumes - when going a little louder I get a peak around 4 khz that is aggravating and tiring. I have tried kimber 8TC instead of the Mapleshades and it is an improvement - more relaxing and full - however I fear that it is the wrong way.

I have opened them some 10 times and I am quite tired of doing it (and have spent a huge amount of money in capacitors). There has been a suggestion to leave the resistor out - will it leave the mids hollow? Do you know what the guys at Mapleshade (that have modified the Gallos extensively) have done? As the tweeter is capacitive instead of inductive, will a Zobel network work?

Thank you for your answers. I am lost - and tired!