Methinks it is time your retired this junk carb and got another one. As long as the unit you buy is complete, the auto choke + secondary throttle vac actuator appears to be functioning and the throttle shafts aren't frozen or have excessive play it is a better starting point for a rebuild. Do a basic '3 part' breakdown of it - fuel bowl/top cover and auto choke: carb body/venturis: throttle plate. Work over a tray, use a piece of cardboard as a template so you can keep track of what screws came from where and keep the high risk components in a zip lock bag (fuel bowl float and pin, brass float and ball bearing, enrichment pump spring etc) Make sure you give each of the individual parts a thorough clean with carb cleaner and compressed air (if you have access to a compressor) Don't pull it apart right down to air bleed jets and disassembling the auto choke mechanism unless you have to. Being patient and observant will go a long way.

*tip for disassembly - give the whole carb a spray of WD40 and allow it to soak. Wipe off the excess. Then as you remove all the screws and disassemble the carb, place the screwdriver tip into the screw heads and give the handle of the screwdriver a tap with a hammer. This will 'break' the threads and make it easier to undo the screws. The number of times you will experience a stripped screw head will decrease (EVERYBODY has destroyed a screw or 2 taking these things apart...)