If you are having trouble removing a Titan Inner Feed roller cover core we have a simple demonstration on Instagram. Wagner and Titan are the same company. Actually Wagner owns Titan and a lot of the products are identical with different model numbers and colors. Wagner is Black and Yellow and Titan is Red and Black. The Wagner inner feed roller covers are made to work with Titan Inner Feed rollers.
You simply remove the roller from your inner feed roller with the black thumb release. Then use two thumbs to snap off the plastic core retainer by putting pressure to the side. You will not break it. Once it snaps off the core will remove from the opposite side. This retaining clip and core belong with the inner feed roller.
You now put the core in your new roller cover and snap the retainer in on the other end of the roller cover. Reattached your roller cover to the inner feed roller and you are set to go. You can watch this on Instagram here: https://www.instagram.com/p/CNm5pSYnmxU/