I once heard that the main drawback of the SU HS6 is that the float ocassionally sticks and then the bowls promptly overflow - cascading unburt fuel down over a hot manifold and possibly igniting setting your precious amazon ablaze while you stand by helpless to prevent the catastrophe...

My problem was not quite that serious...

Shortly after I got my Amazon back from it's bi-annual safety inspection, It ran so poorly I had to roll it home (fortunately the guy's only on the next block).

Anyway, my rear carb bowl was overflowing, and fuel was cascading everywhere.
I took the top off and checked the float settings, jet, etc. Made sure everything was in spec, but after it was back together, the problem persisted. So, grabing my box of su bits, I replaced the float entirely and pulled the quasi-grosse jet and replaced it with a more conventional needle jet.

Funny thing about the jet in there. It's not a real grose jet, there's no ball bearing, but more of a big rounded pin. I've never seen one lke it, but until now, I've only known of the two types...

So, rear carb is back together and the problem is still continuing, so I pulled the front carb apart, change the float and needle (and gasket) and after it's all back together, the car runs like a champ again.

So my questions are these:
Whay causes the thing to stick open and pour the fuel in?
How do I prevent it form happening again?
What sort of jet was in there?