Try our new info resource - "Aladdin's Cave" (Main menu)Just added a separate link to Ash's Dropbox thread (shortcut)
In your last picture you can see the air screw. It is too the right of the T pipe if you look at the picture. It has a brass head and when you remove it there will be or should be a spring. One per carb.
Do you have the brass tubes out??? They will have little holes down the sides.
The brass screws from the float bowls??? If that is it they should be ready for a dip. Take the bank of carbs, the bowls, the tops and everything you have removed to be cleaned. Then all you have to do is put them back together. Polish the bowls and tops. And set the float height which is 22mm on those.
I would not advise someone to take these apart unless they know what they are getting into. There are so, so many little parts to them. But, you can get them apart to change the 0'rings in the T pipes by taking the 8 big cross head screws out of the big alloy rail that holds them together.
I am not in the UK at the moment so can not give you the right measurements. I use Viton O'rings but, you will need something that is fuel resistant. Just looked up a carb kit from Japan and it comes with the O'rings>> http://www.ebay.co.uk/itm/74-76-HONDA-CB550K-CB550F-CARB-REPAIR-KIT-SET-OF-4-REPAIR-KITS-INCLUDE-CI1220-/251460221180?pt=UK_Motorcycle_Parts_13&hash=item3a8c3278fc Does the carb kit from DSS not look like this?