You guys are confused....
Most 428 FE motors came with hyd lifters. You can have a Hyd lifter go bad and the cam will still be in good shape. YES, you can remove the lifters without removing the intake. Do not use a magnet, use as some one mentioned a tool designed to grab the lifter where the push rod sits. Replace the bad lifter then reinstall the rocker assembly. Been there, done that, and it worked fine.