Preamp modifications - who would you use?


I am looking for a company or individual who performs equipment modifications to take a look at a preamp I own and recommend (and implement) parts improvements and or modifications to squeeze out the last bit of sonic performance. I would like to talk with someone who is well regarded not only for the quality of their work but also for their customer service, and who has enough experience and expertise to assess each piece on an individual basis, and not simply apply the same bag of tricks to everything they touch. Based on things I have read, folks that come to mind are Kyle Takenaga at RAM, Bill Thalman at Music Technology, and Chris Johnson at Partsconnexion. I would be interested in other recommendations. Thanks.
mitch2
Check with Joseph Chow at Audio Horizons. He designed and developed one of the most highly regarded preamps around. He has a separate upgrade (mod) business unit, and will make a recommendation once he's assessed your gear. I have been very happy with his work ... great customer service and he'll give you very reasonable rates.
Thanks everyone, you have come up with some names that I didn't know about. Any more I should consider?
I can't recommend anyone, but ask them what type/brand of caps they like for it, and what sonic changes to expect from those caps, or other parts/mods being done. Ask any possible downsides if any apply.
I recently had Kyle Takenaga modify my preamp/processor. You can read my A'gon review here. I've been very pleased with the improvements, which include increased resolution along with a greater sense of relaxation.

I would like to talk with someone who is well regarded not only for the quality of their work but also for their customer service...

Kyle was very responsive both in emails and phone calls. And he was not the least bit secretive about his methods or parts, which was an important consideration for me.

...and who has enough experience and expertise to assess each piece on an individual basis, and not simply apply the same bag of tricks to everything they touch.

I can't comment on this, as I only had Kyle modify a single piece of equipment. A conversation with him about your preamp might answer this question for you.

Sounds like there are other good options as well. Good luck.

Bryon