The 107mm shimano bb puts my 600 cranks' outer ring position at just a bit more than 42mm, and I see the earlier 105's have the same chainline as the 600's. If you do have the older, seven speed 105s (full name: 105-SC 1055) you'll be in business with a 107mm jis spindle.

http://www.sheldonbrown.com/bbsize.html#105

http://www.sheldonbrown.com/bbsize.html#ultegra