I am using a RA23 Celica diff in my KE35, and the width is almost the same as the KE35 one, 5-10mm different. The Sprinter one would not be too much wider. There is lots of room under the KE30 rear gaurds anyway, they need to be filled. I have the T50 in the standard location, and used a TA22 1 piece tailshaft cut down 50mm. This is for the 6.7" diff. If the sprinter diff you are using is a Australian one, it may be a 6.38" diff and the tailshaft bolt pattern and length may need to be slightly different, not sure. You will want to use a 1 piece tailshaft, not the sprinter one.