Yes, you can.
You will need to speak to Motability to explain that you do not want to use your entitlement to free road tax on the ID3. You will then become responsible for taxing it every year (box ticking exercise), even though it’s free.
You will need to look out your certificate of entitlement which came with your PIP award originally. You will need this to tax your other car. You will also need to change the taxation class to disabled too.
It’s a pretty straightforward process. I did it last year.