Can someone help? i have bought second hand a Mr Shifter 2 it has got an alloy plate under the ball, i believe to fit the Alko hitch. My question is are there different sizes of plate for the alko hitches? my hitch is the Alko AKS 3004 and the plate does not fit up to it snugly perhaps they dont. Have mailed shifta products but never got the answere.Thanks Bill