Welcome to iRV2.
Very often the slide drive mechanism , is produced by a different manufacturer than the RV, is there a name on the motor that might identify the slide drive?
Power gear perhaps ?
Are you trying to remove the motor from the gear reduction box, or the whole gear box from the RV?
Anytime you have to remove a pin or bolt from a drive mechanism , you have to make sure all tension is off the connection.
Any chance you could post a photo of what your working on ?
Info on posting photos is in the " FAQ " drop box , in the dark blue bar , under the Google search box.