2007 Saturn Relay Sliding Door

2007 Saturn Relay 6 cyl Front Wheel Drive Automatic

My 2007 Saturn Relay has an automatic sliding door on the passenger side. The middle roller bracket is broken and this made it go off the track.I need to replace this bracket and would like to know what the part is called and about how hard is it to replace. Also can I just remove this piece entirely since it has one at the top and bottom also and just use the door as a manual door without any future problems