TOPIC:

Yes, they do look similar. The Tk27 carbs are made by a company called Teikei (which is, I assume, where the "Tk" in the carb name comes from). The Kz550's and Gpz550's all used Tk carbs of one kind or another, at least in the U.S.

Thank God for small miracles! I finally got this one done! Choke appears to be working properly now (at least mechanically - the carbs are still off the bike again)

I had several different springs, kept cutting one shorter and shorter with no luck - then I realized why I could not get a spring to seat there... the old spring was still there and was NOT coming out (at first I thought something else was stuck in there.
So I dropped the ball in there and... like magic - my choke rod stops now!

Thanks again for all the help!

I should probably update the build thread at some point as I am making progress in other areas as well
(carbs still need 'tuning' - but that is in another thread)

-Lee