I replaced both Nut Power Assemblies. This required taking off the top (6 screws), removing drawer (just tip and lift), removing the front (8 screws), front bottom (2 screws), limit switch (3 screws). Then lift the RAM out, pop the two retaining clips on each assembly to pull the pins and change the assembly. It may be necessary to let the motor run a little to get the ram all the way to the top where it can be pulled out if both assemblies are not stripped completely. After replacing the assemblies place it back in and get the motor to run to start the ram on the threads, make sure to keep the ram level so it starts equally on both sides.