Once I got the strut vertical and one bolt halfway in, I was able to insert the upper bolt also.
The following photo is worth looking at:
You can see the lower bolt is in, but the upper holes are not aligned. The wheel knuckle is hanging down where it was left when I removed the old strut.
I took the wood beside the floorjack here (a 1x4) and put it sideways/vertical under the knuckle behind the disc-brake shield (see arrow). I used the floor jack to push the knuckle up and hinge it into position so that the holes aligned. Then I inserted the second upper bolt.
This bent the shield slightly, and I had to rebend it to give adequate clearance for the rotor.