As with all but the first few 737s, it was assembled at Renton. The door plug was installed in Wichita by Spirit Aerosystems and there were issues with rivets in the surrounding structure that Spirit removed the plug to correct in Renton.

As a result of this Boeing is now refusing to sign off on fuselages with defects found at Spirit to be transported to Renton. And also Boeing will be buying back Spirit, which had been spun out of Boeing by the McDonall-Douglass management that took over Boeing when McDonall-Douglass bought Boeing with Boeings own money.

The fuselage is made by Spirit AeroSystems in Wichita, KS:

https://www.npr.org/2024/06/04/nx-s1-4983722/inside-spirit-a...

The 737 assembly happens in Renton, WA