My solution to strenghen main shafts, and to set 1/8 car torsen diff in the middle looks like this.
http://www.gfoto.com/UserPicPopup.as...B7A443#PicShow
http://www.gfoto.com/UserPicPopup.as...B7A443#PicShow
http://www.gfoto.com/UserPicPopup.as...B7A443#PicShow
1st Tamiya sleeves burned grease off, then drilling to allow cup screw take grip.( not genuine shaft, only for measuring)
Shim plate to sheild bearing side , when STRONG threadlock takes hold on this bushing.
This system allows use of 1/8 T-bones too. No matter where you install big cup as long as axle is 5mm and hole 8mm in cup.