I agree with Dictators comments. No bailiff can turn up on anyone's doorstep or clamp or tow the car /goods willy nilly. As very correctly said by dictator that companies have a strict yet fair procedure they follow this to recover debt or an unpaid fine and this normally happens by sending letters in the post warning the individual. (MANY LETTERS)
Most of the time people either forget or don't bother with it not until the said action in black and white turns up on their door.
Bailiffs do come across as abrupt a**holes but hay they have a job to do and within that job they have heard and seen it all sorts before.
Now the question I ask Mick when you received that old letter you refer to why didn't you act upon it? Or if not you at least someone in the household could off?
Now regarding ownership and liability of the fine. Unfortunately regardless of the car being your fathers and you have documents (receipts) to prove that to be honest they don't mean anything in the situation you are in.
At the time of the vehicle being towed and the information gathered together from DVLA confirms you being the registered keeper and you being the policy holder which be honest makes you liable. Now if you had a whack in the car you would not turn around and say to the 3rd party its my dads car am not responsible because legally your currently the driver of the vehicle, registered keeper and policy holder of the car.
With all due respect I would suggest bite the bullet pay the arrears and let this be a lesson for you.