Michael, i don't think that moving tooth by tooth, then testing is worth the test, I already did this for a couple of nights and things remains the same. Like I said I manage to get a "decent" RMS for the first time, and I think that I cannot do better on playing with the gearing. I might considered buying the belt mod, it not only removing the noise but I saw multiple thread about how "crucial" it is to do this mod. Like kens said it will likely improve the mount performance. I'll be imaging tonight if there's no wind. I will post and image and log to see what you guys think.
Once again thanks everyone,
Theo