Sorry for "raising the dead" so to say, but I just wanted to add my two cents... 
I own a Takky Colour Classic which is now actually fully loaded, containing the guts of a Performa 6500 with a Sonnet L2 G3/500, CS II ethernet, A/V card, and some no-name USB 1.1 board in the PCI slot.
Before going for the full-fledged PPC mod, I actually tried the Mystic mod first (LC 575 boad), in combination with the VGA mod, which was shortly after followed by my Takky 68k mod. After making the necessary modifications to the harness, I dropped in the logic board of a LC 630 DOS Compatible (or was it a 640, can't remember, but it has two memory slots) into the CC and I can say it worked like a charm. General video tasks on the Mac side were ever-so-slighly slower than on the LC 575 due to the 580+ models using regular RAM rather than dedicated VRAM and getting ATA/IDE to work properly was ... uhmm yeah ... fun ... but other than that it actually performed really well!
Being able to switch between Mac and PC environment on a fly, all self-contained within this little beige box with that tiny 9" Trinitron color tube, I have to admit that this definitively bought my inner geek out of me. Too cool. I've used this setup for quite a while but due to my insatiable hunger for more Power(PC) I ended up replacing this board with the Performa 6500 logic board and couldn't be happier.
About a year ago I acquired a Performa 6200 Road Apple for very cheap, tossed the board since I really just needed the case (I played around with it for a bit, and yes, they definitively deserve that title) and dropped in the LC 630 DOS Compatible. This has become my main 68k machine which I hope I'll be able to keep running for as long as I can. It may not be a top performer or the most visually appealing machine when comparing it to the other 68k models, but to me this setup is a prime example of "ingenous professional hardware hackery" which makes it quite unique to me, especially when considering that what we now can do at ease and on the fly in software, e.g. through emulation, actually had been implemented in hardware a mere decade or so ago ... again, this is just my inner geek speaking again.
-- BeniD82
I own a Takky Colour Classic which is now actually fully loaded, containing the guts of a Performa 6500 with a Sonnet L2 G3/500, CS II ethernet, A/V card, and some no-name USB 1.1 board in the PCI slot.Before going for the full-fledged PPC mod, I actually tried the Mystic mod first (LC 575 boad), in combination with the VGA mod, which was shortly after followed by my Takky 68k mod. After making the necessary modifications to the harness, I dropped in the logic board of a LC 630 DOS Compatible (or was it a 640, can't remember, but it has two memory slots) into the CC and I can say it worked like a charm. General video tasks on the Mac side were ever-so-slighly slower than on the LC 575 due to the 580+ models using regular RAM rather than dedicated VRAM and getting ATA/IDE to work properly was ... uhmm yeah ... fun ... but other than that it actually performed really well!
Being able to switch between Mac and PC environment on a fly, all self-contained within this little beige box with that tiny 9" Trinitron color tube, I have to admit that this definitively bought my inner geek out of me. Too cool. I've used this setup for quite a while but due to my insatiable hunger for more Power(PC) I ended up replacing this board with the Performa 6500 logic board and couldn't be happier.
About a year ago I acquired a Performa 6200 Road Apple for very cheap, tossed the board since I really just needed the case (I played around with it for a bit, and yes, they definitively deserve that title) and dropped in the LC 630 DOS Compatible. This has become my main 68k machine which I hope I'll be able to keep running for as long as I can. It may not be a top performer or the most visually appealing machine when comparing it to the other 68k models, but to me this setup is a prime example of "ingenous professional hardware hackery" which makes it quite unique to me, especially when considering that what we now can do at ease and on the fly in software, e.g. through emulation, actually had been implemented in hardware a mere decade or so ago ... again, this is just my inner geek speaking again.
-- BeniD82