'89 roller-cam LA 360 w/Magnum heads - new roller lifters not pumping up

sorry for crashing this (indeed very very interessting thread), but how bad, if the plunger is stuck into the lifter when trying to disassemble the lifter. I´m asking, coz i´m just started cleaning mine, and non of the 16 lifters from my engine will allow me to pull that plunger out. cld. it be the reason, that i have put them in solvent and put them i a ultrasonic bath ??

should that plunger move easily ? or is it common to use some "force"

everything else on the lifters works freely an looks nice after the ultrasonic bath - checkball etc..

cld it be that the plunger is hold by something like a "hydraulic vaccumm" ?