the later ones are pretty easy too. Just have to move stuff in the engine compartment, and the fan itself comes out the same as it always did.
They make these fans with non-serviceable bearings, unfortunately, and it can be very hard to get the plastic blade off without breaking it. However, if you are really stubborn you may be able to get it open and lubricate the bearings.
I believe on one long ago I actually just drilled a hole in the end cap, oiled it and then stuck some putty over the hole. It lasted a while at least. You can sometimes work a little oil into the fan end, and may even be able to do this without removing the fan if you can get a piece of wire or a bicycle spoke, etc. down to it, and drip the oil down. This will still not help if the bearings are already toasted or if the brushes are squeaking, though, so a new (aka junkyard) fan is probably more rewarding.