I have had to move the circlips to the central position 3 on my 500 carbs. I was able to remove the two screws at the base of the slider/plunger without the need to remove the plunger arm from the slider first. I just removed the bolt at the pivot end and slid out the the gubbins.
Many folk here will know how fiddly it is putting the two screws back in place with the arm still in place so thought I would share my tip here. As a former Tropical fish keeper I still have odd bits of Neoprene & Silicone air line pipe (5.5mm ish o/d) in my garage. plus an old bit of steel similar to a barbecue skewer.
The Silicone tubing I found best as it was easy to push the head of the screw into the pipe so you have a length of tubing that will easily reach the bottom of the slider. I then placed a metal rod that was a loose fit inside the pipe to give the pipe a little rigidity.
This enabled me to place the screws visually in line with the thread in the slider - by turning the pipe with my fingers it was very easy to screw them in with no fear of a crossed thread. When both were in place fully screwed down by just using the pipe I was able to easily nip them up with a JIS tool. The Silicone pipe is easily pulled off the screw head when it is done with.
This tip is for us amateurs not the former professional here.
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PXL_20231013_095540299 by
Macabe Thiele, on Flickr
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