do aftermarket mkiv supra sway bars bolt to sc300's with no modifications.

 

Then you didn't search well!!!

There are probably 100's of posts stating that the front does but the rear would also need the addition of Supra sub-frame mounts.

Brush up on your search skills.

 

Make sure you adjust the number of pages your window sees at the bottom of the screen. Maybe it is only set to "1 Month"...set it to "From the beginning".

As was stated...there are copious amounts of information on this topic.
Good luck on your next search.