I just made a tool since I got tired of busting off the crown pieces and resorting to a channel lock. Yes the crown head pieces tend to bend out when pressure is applied. I found a PVC straight connector ~3" long (cant remember what diameter size - probably ~ 2" or so) that has a small raised ring in the inside equidistant from both ends. The raised ring just fits over the crown of the filter. I used a metal ice pick that is about 5" long with a nice wood handle. The pick part is about 1/4". Drilled a hole through the center of the PVC connector (across the diameter of the connector) centered just a hair below the raised ring. I made sure the hole was a tight as possible on the ice pick (no slop). Stick the pick through the hole, place the whole assembly over the filter crown and twist away. Next mod - make the ice pick metal square instead of round since I really have to put lots of down pressure to keep it on the filter. Actually, a little taper will work to help it dig into the crown pieces just a bit. Caution - a tri-corner file will cut the crown pieces off.
I am so happy since I know I wont have to have my usual battle with this next year.