If you have the 2-shoe clutch adapter, you are fine using those clutch bells in the links you provided. The 2 shoe adapter looks like this
HERE:
If you have the 3 shoe clutch adapter, than you need larger 1/8th scale clutch bells like ones that came with the RC8 kit originally. The 3 shoe adapter looks like this
HERE:
Losi 8 Buggy + Truggy & Associated SC8
Tekno RC Conversion Kits on all
MMM, MGM, Xcelorin ESC's
Tekno Neu "square can" brushless motors
Polyquest - Neu - Flight Power LiPo's