Ok, got them off. What a PITA that was. They fought me the whole way, but I prevailed in the end. I have no idea how I'm going to get them back in though!
And as I feared, it was a mess in there - and for some reason, the gas remaining in them had turned a weird shade of green! Even the floats have been tinted green from it. The float bowl drain holes were clogged, there was visible crud throughout, and the float valves were basically cemented in place; I had to un-clip them from the float and then work them out using a pair of very fine needle nose pliers to break them free.
The float bowl gaskets have seen better days and need to be replaced, and the float valves have some noticeable indentations on the rubber tips, so those need to be replaced as well. I didn't have any problems loosening up the phillips head screws, but I guess now would be a good time to replace them with some stainless socket head cap screws as well.
I tried to find some kind of rebuild kit for these carbs and I couldn't find anything. Can anyone point to a source for at least the bowl gaskets and float valves? I can probably find the replacement screws over at the local ACE hardware store.
As a side note - there are a few rubber bits on the bike that are cracked and/or falling apart that really could use to be replaced. Where can a person find parts diagrams for these bikes so I can trace down some part numbers, and where can you get OEM parts other than my local supermarket dealer that charges a kings ransom for just about everything. Does that Triumph place in Georgia that we went to a few years back sell parts?!? I know they have hats and cigarette lighters

Cheers,
Brad