Start with one system
The instinct when standing up a function is to build a framework covering everything. It produces a long project and nothing usable, because the requirements differ per system in ways that are only discoverable by working on one.
Start with a single AI feature, chosen deliberately. The best candidate has three properties: it matters enough that failures have visible consequences, it is already in production so real usage data exists, and the team owning it is willing rather than conscripted.
That last property is worth optimising for even at the cost of the first two. A willing team gives you access, honest failure examples and a collaborator. An unwilling one gives you a political problem before you have any results to point at.
Build the whole practice for that one system: evaluation set, thresholds, gate, and the reporting. Then use what it produced as the template and the argument for the second.
The reason this sequencing works is that the artefacts are far more persuasive than the proposal. A demonstration that this feature degrades on a specific population, or that a provider update moved behaviour last month, changes minds in a way that a framework document does not. Find that first, then generalise.

