.
It is very heard to remove them thru the piston bore, from the out side. The space is limited, even if you made a hook type puller the B2 band would be in the way.
The easiest method that I found is to remove the valve body and plate, Then remove the B2 band guide by pulling it out of the case, once removed you will have greater assess to the B2 piston seal and bushing. With a brass drift punch, tap the original aluminum bushing and seal out of the case. If you are lucky the seal and bushing will pop out if not then from the piston side crush the seal in, too loosing it then tap the bushing until it comes out. Caution: the B2 seal and updated plastic bush gets installed from the out side of the case, thru the piston bore. Before you start make sure you have adequate clearance. I would post some pictures but they are not up on my web site yet.