Craig, you say you only had 3rd Party yet they gave you money for your car???
Don't think there's a 'statute of limitations' but you'll still be quizzed as to why it wasn't a priority earlier and what's changed to make it important now.
Also no point in going to court without all appropriate documentation, i.e. original copy of 'letter of demand', original quotes for repair, all liaison with previous insurance company and monies already paid, witness statements, an accurate recollection of dates and events, etc, etc.
If you do still decide to go down that road, I'll serve him for you at no charge also.