They can screw them on the spare parts later. All dealers do that.
Spare parts has always been where the big money is. I’m amazed that older Aircraft can be kept airworthy with the bizzarre cost of replacement aircraft parts.
I use to buy aircraft replacement parts and I would go into sticker shock every time I got the latest price increase on parts. It should be almost criminal, the yearly price increaces on parts.
When an Aircraft goes out of production, buying replacement parts goes through the roof. The long term parts support of an aircraft is nothing like it is for say a car.