Must cleaning your IKO LWLC-9-B rail perfect because a little durst can cause to fail to install.
Put lubricating oil on the IKO LWLC-9-B Block rail.
Must be keep perfect alignment to install the IKO LWLC-9-B Block. In some case, no enough space to install IKO LWLC-9-B Block and you need to uninstall the rail to install it.
Loose 4 screws to let the IKO LWLC-9-B Block can go to the rail easily.
Put IKO LWLC-9-B Block gently to the rail and sliding slowly the whole block.
Then tight the IKO LWLC-9-B Block’s screws correct to keep the IKO LWLC-9-B Block perfect to fit the rail.