Did you remove the end link on the stabilizer bar? Makes it a lot easier to move that lower control arm. If your car is fairly new and really clean underneath, you can also undo the stabilizer bar bushing bolts (the ones that hold the bar up across the middle of the car), to get a little easier movement on the control arm. But sometimes those bolts are really rusty and break, and then you've gotta drill and tap. That'* why I just undo the links. Unless the links are pretty new, you will probably need to destroy the old ones to get 'em out, but new ones are not expensive and are simple to install.
If you don't have help, and the arm is still really tight, loosen the big nuts that attach the lower control arm to the subrame rail. That will allow the rubber bushings to spin and the arm will move much more easily.
Oh yeah, make sure the drive shaft is all the way (snapped) into the trans on its snap ring. If it is sticking out too far, the alignment will be wrong on the ball joint post making the join-up with the knuckle difficult or impossible.