Tell us how you were adjusting them. Now A little flat tappet cam knowledge,when the cam lobe comes around and starts to lift the lifter,it doesn't hit dead center and doesn't just pushup on the lifter. As it pushes up since it's pushing off center the lifter spins as it goes up. Since the lifter spins it prevents the lifter and cam from just wiping across each other,which wipes down the lobe and takes the crown off the lifter,because they are rubbing not spinning. InCam and a lifters are also splash oiled and work hardened,so you have to keep the rpms up for the first 20 minute,just to be sure there is enough oil while the cam and lifters harden. Too stiff of springs on break in is another cam killer,excessive pressures before the cam has work hardened. Anyway if your lifter still has a crown you very likely will get away with swapping it. If it's flat or dished the cam is likely damaged also.