Do you have the easel locking mechanism installed? Extras might be part of that.
You need short neck european bulbs made by OSRAM. Ph111,112,113 are too long and will cause uneven negative illumination. Either light or dark edges, I forget.
Last ones I saw for sale recently were at Glenview.com. They are scarce, very scarce, so stock up. I would run a voltage reducer to make them last.
http://www.glennview.com/
The closest you can get otherwise is a snowy white 60 or 75 watt domestic, again I forget. Acetone will take off the lettering. Domestic incandescents are going away too, so take action.
PH 111 will not work if you expect the Leica quality to show.
The large easel is thicker than the small one so you need to raise the clamping position on the column. There is supposed to be a pin to go thru the holes to make the new position higher up. If you do not have the correct start ( clamping) point, AF will not work perfectly. The clamp height needs to go up around 1/4" for the thicker easel. Use a wooden dowel if you must.
Set the focus at 10 X, lock it in with one of the two hold downs that slide around the focus mechanism. Then bring down to 3 1/2 X and use the thumb screw
that sits against the focus cam to establish focus. Then it will work 3.5 to 10 X perfectly. Original Leica Focotars will make up to 8x10, optimized for 5x. After that corners go bad. Later lenses worked better,
There is also a anti newton slip on "filter" that fits over the condenser. Buy one if you can & it will cost dearly.
The second clip around the focus barrel is for setting focus point on paper placed directly on the baseboard, no easel.
The extra bushing may be part of a pair that runs on focus cam. I will check mine.
The plates may be for holding the easel clamping lever. Mine is a later model and may not have exact same thing.
You can solve the bulb problem if you get a new bottom housing from a grey one with the egg shaped head. with filter drawer.
Edit
My enlargers are white base without easel clamping. The wood base one is long gone. The older one seems not to have any column holes at all, but i modified set up and don`t wish to disturb it.
The other has the hole and pin, but I have it clamped above for some reason. Been that way way too long to remember why. Again mine works and I do not wish to disturb it.
The bushing is for the focus cam. Looks like you have a spare.