Step 1

First off we will need to remove the nut covers. A knife or flat head screw driver will work just fine

Step 2

After we have removed the nut covers we can Remove the bottom leg locks screws.

Step 2-1

Here if you look closely we have removed the two bolts and two screws.

Step 3

Now we can start to remove the leg lock pull and twist leg lock and it should detach from the middle leg tube and will allow you to remove the lower leg.

Step 4

Now we remove the rubber foot from the bottom of the lower leg tube

Step 5

From the end that we removed the rubber foot slide your new leg lock on largest opening first this will be very important very soon.

Step 5-1

You are going to Slide the leg lock all the way to the other side of the lower tube

Step 6

Now your going to grab your tripod and push the part of the leg lock that is sticking off of your lower tube onto the middle tube be sure to align the two leg locks so that they are uniform it makes it easier when extending the legs. 

Step 6-1

Now you are going to tighten the piece of your leg lock that is on the middle tube so that you wont worry about it falling off. 

Step 6-2

Now the lower bolt needs to be tightened to your leisure some people prefer a tighter lock it is a personal preference