100 Series Diff Lock Actuator (genuine toyota)

Hi, wondering if anyone has any knowledge/experience with the diff lock actuator on the rear diff of a HZJ105R. I pulled mine off as a result of a malfunction, found it to be full of mud and dirt, doesn't surprise me, so cleaned it all out, all good.......however now I don't seem to be able to get the rotating cam in the right sopt to operate correctly. No literature from Toyota on such issues, nor google, any suggestions appreciated.

Thanks Big Al