2wd DO have cam bearings, in the form of a normal ball race type.
These simply slide off the cam when the pulley is undone etc, dead easy.
They are in a carrier that is clamped between the head and the front bearing supports.
To do simply loosen belt, take off cam pulleys, undo bearing carrier and other cam posts, lift out cam, remove woodruff key, slide off the front carrier housing the bearing, take out bearing and replace, think it is a circlip holds it in/stops it moving, you'll soon see it's dead easy.
tabetha