Yes, the car has to be in neutral when swapping it out.
There should be markings on the NSS (with it not installed), to tell you what position it is in.
Take it back out, put it back in the Neutral postion, and re-install it with the car in neutral.
Steve - TCCoA member
2003 Crown Vic LX Sport
1995 T-Bird LX 4.6 retired at 247,888 miles
Thanks for the ride !