Anyone tried different focus screen on digital?

[Jay Taylor]

Merry Christmas/Happy Holidays everyone out there in PDML land. I am 
wondering if anyone has successfully had a different type focusing 
screen installed to replace the stock one on any of the digital cameras 
*istD, DS, DL or DS2? I am assuming this would be something that an 
authorized Pentax service center would need to for someone if they 
wanted it or would it be a fairly easy DIY install? Not that there is 
much lacking in the stock focus screen/viewfinder, but I was just 
looking thru my old Minolta X700 with the horizontal matte field with 
central split image focusing aid that perked my curiosity. I've seen a 
few posts on focus screens, but no real testimony of these being 
modified on the digitals.

Thanks,
Jay T