I had a heck of a time figuring out the detachable lock for my TourPak. Sorry I can't remeber how I finally got it working, but it was a PITA. I eventually figured it out. The instructions are worthless.

As far as the key fitting....same problem! I had to bend the shaft of the key about 45 degrees (using a vise bend gently by hand) to get it where it would fit easily. Be sure that the bend is oriented correctly so you are not fighting the supports on the side of the detachable bracket.

Andy

 

On the lock not wanting to latch you are going have space the the bushing out to center the lock in the groove, if it's hitting on the inside of the bushing you'll have to take a washer out to center it. I don't know why it's that way, but I had to do it on mine too On the key DON"T put to much pressure on the part that goes in the lock, you'll snap a very small screw off! ( Don't ask )