In my mind, not much different than a multiple part run.
Your feasibility is not much more than a contract review..."can we make it? Do we have capability?".
Process design and development would involve laying out your process steps or developing your shop flow card across your current equipment.
Product/process validation could involve considering your machine capabilities based on like parts and appropriate in process inspections as defined during the development stage.
Feedback/assessment/corrective action could involve a review of all inspection information after the job is complete, effectively the APQP team asks the question did we make it correctly. The feedback part of it could involve changes in the company's mindset as to what is feasible.
In my mind, if you can show process planning and critical evaluation of what you plan to do and what you did using a cross functional team, you're practicing APQP.