A neat car.
Kind of the Japanese Camaro, although far more sophisticated in design and execution.
I'd use a good 10w30, your choice.
Were it mine, it would be the perfect host for the Pennzoil Platinum and Quaker State Torque Power 10w30 I have in my stash.
Maybe a couple of short OCIs just to make sure everything is fairly clean?
This car sounds like a nice find!