Hahaha Datsun works!
Uhhhh I'd say none of it at first, Ultium. Until they take over the power unit from Alpine(Datsun!), there won't be any Ultium in there. Once, or if, they take the power unit control in-house, then it'd be an Ultium powered unit.
The reason, at least how I see it, is because Alpine will still making their own power unit for their own cars. They won't want one power unit they're producing to have their electrical system and then one to have a GM electrical system. That would add unnecessary complexity to the R&D of the all-new power unit and it would likely make both units worse because there is a cost cap for the teams and this would, undoubtedly, increase the spending.
After trying to look into the cost cap regulations, the engine cost cap are different and I can't find the specific regulations regarding how the engines cost against the cap.
"
What comes under the F1 cost cap?
Any expenditure related to car – but not engines – performance is relevant for the cost cap. This includes:
All parts on the car (from the steering wheel to the wheel nuts)
All the elements needed to run the car
Most of the team personnel
Garage equipment
Spares
Transport costs
Everything in between
The biggest area of focus is car development costs, with teams having a weigh up what is developed, how much is spent on each part which is manufactured and how many of the parts are needed and can be afforded without overspending.
What doesn’t come under the F1 cost cap?
There are several big-ticket things that aren’t covered by the cost cap, including:
Driver salaries
The wages of the three highest-paid staff members
Travel costs
Marketing spend
Property and legal costs
Entry and licence fees
Any non-F1 or road car activities
Parental and sick leave payments
Employee bonuses and staff medical benefits
Engines – which are more complex because some teams make their own while others buy them – are covered by their own set of cost regulations."
https://us.motorsport.com/f1/news/f1-cost-cap-what-is-it-how-it-works/10379800/