No parts are missing. The #2 carb has a non-adjustable slide. Use #2 as your reference carb and balance the other three to it.
Why do you want to pull your carb bank apart? Unless you have leaks in the fuel gallery tubes between the carbs, clean them while they are together.
The stubby brass jet is the idle jet. On later carbs, they are pressed in. You can pull them out with pliers. Just be careful you don't crush them.