This new to my shop CK12 has got me stumped. While going through a cleaning and service… I found this mystery part … while inspecting and adjusting the end play of the cross slide thrust bearings. I cannot find a pic in the parts manual ( that I have) nor can I find any mention of it , or function, in the operating manual. I even checked other Monarch machine manuals of the era. The thrust bearings are housed in a threaded piece about 2 inches long. There is a locking screw on the square block ( that the manual calls the bearing block or housing). There are two castellated pieces that will engage each other after a grub screw is loosened on one … and slid together. The lead screw is then engaged and will turn the threaded bearing housing. ( as long as the locking screw is loo).There is not a big range of motion . What function is this. I have searched every pic and forum thread on the internet and can’t anything. Any help would be appreciated! Thanks