There is a tiny bit of technique to it.  If you can't get it, just send it on over and I'll take care of it.  You have to keep the amount of solder on the tabs to a minimum.  If you can't get it to fit with the wires on the bottom of the case, turn it around and try it with them on the top.  SOMETIMES, it can be a little easier.

Call me with any problems.

Chad