losi
the gear ratio in the cr an the MF1 are the same 243:1. all u will need to do is get the diff gear, tranny case and the tranny screw set.... possibly longer dogbones, not sure what size the mf1 takes, in my mf2 they were .215 short...I used bones from a mf1 but I don't know if they were the stock ones. If u need more help I cn measure the bone length for u... One thing I did notice last night while tuning on my backyard track was the moly grease I put in the diff may be to stiff, it seem to be acting more like a posi traction..(while cornering) I am going to change to the losi silicone grease and use just enough for lubrication...