It has been a long time since I’ve done this, but if I remember correctly the other side of the greasy joint shown in your photos is covered by a thin metal plate. You have to remove the metal plate to expose the end of the axle. The axle is held in the cv joint by a snap ring/circlip. Remove the circlip and the axle can be pulled out of the cv joint.
Alright, I only did this a month or 2 ago. Take off the exterior metal caps (you can take off both at the same time, doesn't matter) and wipe away the grease. You can take them off with a flathead and a hammer, or you can try a more gentle approach. There should be some large O-rings under there, so they might be a little difficult to get off. After you wipe away the grease, you should see a circlip at the end of the shaft. Remove that. The whole assembly should come off, whether you pull it off yourself or use a press. Once the bearing assembly is off, take off the other cap if you already haven't, and spin around the bearing race and ball retainer until the balls come out. Don't force the assembly in a direction it doesn't want to go, you could hurt something. After most of the balls are out, the race and retainer should come out as one. Tilt the race on its side and rotate it around until it comes out of the retainer. Done. Assembly is that in reverse, but make sure everything moves freely and doesn't get caught on anything. If it's assembled wrong it will be locked in place and you'll have to gently tap it around until you can take the inner assembly out. Once you get it out, rotate the inner race one groove over in either direction and it should be free. Don't use grease when you are reassembling it, it won't move very freely. Sorry, I know that's a lot to take in.
Yes tap the outer cover off clean away the grease then remove the circlip. Now the hard part to seperate the axle from the CV on GTV6 and Alfa75/Milano you usually need to use a shop press if you try to hammer the axle out of the CV you can often mushroom the end of the axle shaft closing the recess for the circlip to the point that the axle will not pass through the CV joint, Do not try to force the axle through the CV, if after a few hits the axle does not move I suggest you use a press.