How much of the space shuttle Enterprise is still flightworthy?

[Ranchoth]

…that is, could be cannibalized to put on a flight-ready shuttle orbiter (if there were any, at the moment), or wouldn’t have to be replaced if you were to refit Enterprise into a spaceflight-ready vehicle?

Enterprise being, of course, intended to be completed as a spacecraft, but design change during development making this uneconomical. But I’m curious about, after all these years, and being in two museums, you’d be able to use anything but the frame and the paint.

[aNewLeaf]

The link you give says it’s not much of a space shuttle, most of the subsystems were never installed and there’s no heat shield.
It was not an orbital craft when it was new, and after being maintained as a museum piece it can’t be in any sort of flightworthy condition.
The frame might still be solid, but the craft is the wrong shape, per your cite. So other than as a a source of scrap metal, my assertion is there’s nothing left that could be used for space flight.

Edit- wiki says:

The design of OV-101 was not the same as that planned for OV-102, the first flight model; the aft fuselage was constructed differently, and it did not have the interfaces to mount OMS pods. A large number of subsystems—ranging from main engines to radar equipment—were not installed on Enterprise, but the capacity to add them in the future was retained, as NASA originally intended to refit the orbiter for spaceflight at the conclusion of its testing. Instead of a thermal protection system, its surface was primarily covered with simulated tiles made from polyurethane foam. Fiberglass was used for the leading edge panels in place of the reinforced carbon-carbon ones of spaceflight-worthy orbiters. Only a few sample thermal tiles and some Nomex blankets were real.[4] Enterprise used fuel cells to generate its electrical power, but were not sufficient to power the orbiter for spaceflight.[5]

Enterprise also lacked RCS thrusters (which were useless in atmospheric flight) and hydraulic mechanisms for the landing gear; the landing gear doors were simply opened through the use of explosive bolts and the gear dropped down solely by gravity.[5] As it was only used for atmospheric testing, Enterprise featured a large air spike mounted on its nose cap which had been used on the U-2 spy plane.