Hi Gordon,

Pic 1: You can remove the Plastics, just get a pair of pliers and pull them off. I do that 99% of the time.
Pic 2: You must plug that. Get some tygon tubbing, heat it up and one end with a ....lighter and pinch them together when is hot enough...or pinch the brass shut and solder.
Pic 3: Take the spring from curent position and put it on the curve between the 2nd and 3rd hole. look at my pic. Pulse hole is correct.
Pic 4: Yes you can remove it if you like....but why? if is to long...you can cut it. It will make it easier to prime the carb. You can remove also the thootlle adjustment position since you get it on the servo and you will position with that. however
it my get idle sensitive and you will relay on the servo. If the screw is there ...then will hold that position all the times.

This carb can pull gasoline from 1-2 feet away easy. tank can be below ,above center carb.

Hope it helps