Anyone had the equipment customized ?

" the deeper you go the higher you fly ". Right. But you also got to land safely.
Larry, that's extensive modifications/customizing. Impressive.

Back when I was much younger and was just starting to build a system with separate components with my first pair a Magnepans, I couldn’t keep my hand off the soldering iron. I would mod everything and with the modest equipment I had in those days it improved what I had. Did several mods for friends that actually had much better gear than me at the time.

With what I own today I would never dream of modding my equipment now, and honestly it sounds so good I’d be afraid I’d mess up the sound. Modding today for me is cables, isolation devices, room treatment, power receptacles and etc. Used to build my own cables when I could build better than I could afford, but again happy with what I have. One thing I have done inside my gear is change out the fuses but that’s as far as I’ll go.

Oh, if I picked up an old Adcom amp, it’s game on.

I had Noble Electronics modify a DAC. It came back a different unit, sound much improved. However, the money paid for these services is almost never recaptured when you sell the unit. In my case, about $1000.

When I was modifying equipment and making money at it, I found some horrible stuff that came in from folks who someone modify it but didn't know what they were doing.   One crossover came in the shop and the guy used acid core solder on all the connections.   Another had such bad workmanship, I had to rebuild the entire thing and fix it before I could modify it.  

If you go this route, make sure you go with someone who knows their way around an electronics lab and has impeccable workmanship.   Take a gander at some of the work they have done in the past and get recommendations.