Just write a cheque from your account to your fathers account , if its the same bank regardless of branch its instant transfer after cheque clearance , after your father receives the money in his account , he can make a payorder from his account to the showroom.
If you buy the car in your name (pay order was from your account) then you'll need to register the car in your name and then transfer to your fathers name.
Direct registration to your fathers name if the invoice is in your name will cost approximately double the registration cost.
So my advise just transfer the money in your fathers account and make payorder from his account , and book car in his name. This will also show him as first owner in registration documents and will be a plus point whenever he wishes to sell the car.