First you need to go to parameter mode and find your chuck/tailstock screen and turn on the center work bit to make the tailstock active. You can then program the quill using M56/M55. Foot switches will become active as well.
In order to move the body, you will need to loosen the 2 bolts on the front of the body and push the body to it's new location. It's probably stuck in it's position if it hasn't been moved in a while, so get out your pursuader and give it a couple whacks to jar it loose. (soft BFH preferred)
It's an option to have quill position confirmation on the machine, but if you do, you should have some indicator lights on the front panel and a rod next to the quill that moves with it. You will have to adjust the rod "dogs" to get the limit switch to come on when it is in the correct position. They are under the plate on the top of the tailstock body.