String sizes and other advice needed

["James Ko" <Kojaque@email.msn.com>]

Hi all, I would appreciate some advice on string gauges and computer
recording.

Question 1:  I decided to turn an old, standard scaled electric guitar of
mine (an 80's G&L SC-3) into a lower register guitar.  I want to get down 
to
a B or C on the 6th string.  What string gauges would be necessary to keep
aproximately the same tension as if it were strung up in standard pitch 
with
9's or 10's?  If anyone plays a 7 string, what gauge is your lowest (B?)
string?  Also, I know there are some Crafty Guitarists out there:  What
gauges do you guys use especially for your 6th string?

Question 2:  It just so happens that this guitar has it's original 
Wilkinson
roller nut that unfortunately will not accomodate anything larger than a 
set
of 11's.  Does anyone know if they make these roller nuts with large spaces
for thicker strings or will I have to bring it in to a repair guy for a
regular nut?  With the present set, I can only get it down to a D and even
that is on the slack side making playing with proper intonation difficult 
on
lower fret positions.

Question 3:  I have ordered a non-SCSI computer recently and am thinking of
using it for recording.  How necessary is it to be SCSI for recording
hardware/software to be effective?

Thanks alot

Jim Ko