Yes, they can be removed. Remove the head and the head end o-ring.
I use a loop of paracord about 12" long. Loop under the clip and tug. Usually a few sharp strong tugs will do it. Be aware that there is a small plastic shim under the clip where it is attached to the body. Do not lose it!
One possible side affect is the o-ring tends to squeeze out where the clip was.
Mark