Rear lower control arm
 

I need to replace a bent rear LCA on a 325i. I've read several posts regarding getting the upper bolt out. One such post provided a BMW P/N for what I understood was a shorter bolt so I cut off the original bolt and purchased said bolt only to find it was still too long. At that point I set out to follow another post that suggested that it's possible to remove the mounting bolts from the differential and move it to allow the LCA bolt to be replaced.
I have the vehicle supported at the rear jacking points. While supporting the differential I loosened both rear bolts. When I removed the 1st bolt instead of the rear end coming down as I expected the vehicle dropped about 1/2 inch. I've tried to jack it back up but everything moves together. I'm hesitant to remove the 2nd bolt until I know I can realign the holes after getting the new LCA reinstalled.
Am I supporting the car at the wrong spot? Also this particular post mentions a support bolt on the side of the differential. I'm not seeing this. Is it on all 352's?