How to remove these taps?

Thanks for that, mine is the second type as there is no grub screw in the spindle. The problem is he shows it with the centre cap already off and that’s the part I need help with.

Thanks guys. So maybe the screw is under the small white disc with Hot or Cold written on it? Again, I don't want to damage that by trying to pry it off if it's just decorative and not the access point for the screw. The whole cap part does seem to be separate from the handle body but there really isn't much of a gap to get a blade or screwdriver in there and believe me I've tried. I'll try turning it instead to see if it does screw off.

Hmm.. A vise grip could also ruin it if not done very carefully!

Not so easy after all. Got the hot one off using a plumber's grip and a tea towel, not without slightly damaging the chrome but it's not bad.

The problem is the handles don't seem to fit on the other tap spindles. I tried it in reverse and was able to put the handles I want to replace on the taps which had the chrome ones by gently tapping them with a rubber mallet. However I tried the same thing with the chrome handles and couldn't get them on. I didn't want to knock them too much in case I broke the sink.

They're all Gattoni taps and I replaced the upstairs bathroom plastic handles with these chrome ones several years ago so it should work. Do the spindles and the part of the handles that fit onto them come in different sizes? If not, can anyone suggest how I might get them to go on?

Here's what each piece of the puzzle looks like:

Ok thanks. It will be hard to measure them accurately I think and to count the teeth as they’re very small. I’ll give it a shot though. The thing is we had what I thought were the same taps upstairs and those chrome handles fitted fine. So they mustn’t actually be the same. Maybe I’ll check it with a Gattoni dealer, if they’re still around. That’s where I bought the chrome replacements about 12 years ago.