I haven't ever had to. I just blow with a 80 psi of compressed air from inside the bowl to clear the filter net on the other side. Usually just replacing the needle itself prevents leak issues. I believe the old plug needs to be drilled out but Morley would know for sure.
I was always under the impression that when you change the needle, you change the seat (plug?) as well. :confused2: But if you have to drill it out ... what a pain. Can see why you'd only replace the needle then.
Curious too as to what Sean has to say about this too.
id like to know how its done! the carbs im rebuilding and putting a jet kit in, had one needle seat that had been rubbed into a groove and the needle itself froze in it. it came out covered in film. so after looking at its replacement in the rebuild kit i tried soaking it in parts cleaner overnite and pressing it out the top.... and really screwed it up. see picture. so can someone tell me how to remove?