MOTM

I vote for 4a.  Those few who oddly voted for just 4 didn't give any reason 
for wanting those two jacks squashed up near and possibly interfering with 
that knob. Not to mention being a less attractive jack layout visually.

Numbers are useful for writing down patches.  However, it is relatively 
simple to count bold tick marks and write it down anyway.  But if numbering 
is done, the neutral setting of the knob would determine how.  If the center 
position of the knob is no shift, then that would be marked 0, and it would 
go negative to the left and positive to the right.  If the knob set all the 
way counterclockwise is no shift, then that would be 0 and the dial would be 
all positive.

-Elhardt