I bought a HM Strat a few month ago, and I couldn't get the Kahler trem to work properly, no matter what I tried. I am a Floyd Rose player so I should know how to set it up, but I guess the knife edge studs was worn (looked like it!)
Anyway, I was beginning to think of just making over the whole guitar, because I have no H-S config guitars, so I thought that filling the mid-cavity, and maybe even make this my Sustainer guitar (when I can afford a Sustainer/Sustaniac kit).
But I also obviously had to change the trem. Instead of tracking down some super rare Kahler parts, I decided to go with Gotoh Floyd, which is my favorite bridge anyway.
And before I drilled I just had the crazy idea of trying to fit the stud right in the wood hole, after removing the Kahler stud... And WOW!!! It actually fits, and REALLY HARD too. It's like those old school OFR wood screws.
This is like the easiest trem swap you could do. For some reason I installed a bad volume pot (I get like 5% of the signal...), so I can't check tuning and intonation properly, but I am pretty sure it's possible to intonate the bridge too, but I haven't got to really try that out yet.