An interesting question arose elsewhere. Suppose you break out a "New, Old Stock" item. It is UL-approved and has UL-approved instructions.
The instructions say to do X.
However, since the item was UL-approved, NEC has changed. Doing X is now explicitly forbidden, and you must do Y.
Which one controls? Are you obliged to follow the instructions?
Are you obliged to follow current NEC?
Are you obliged to throw the item in the trash and get a modern one whose UL-approved instructions are consistent with NEC?