If you dont get the offer you want, you could always try to claim directly off the other fellas insurance, they might contact you directly to settle anyway so that they can minimise costs.

If you're not happy with an offer you can accept an interim payment to get you some cash, start checking around for similar cars to yours so you have evidence of what it's worth, unfortunately the book price will be cr4p but we all know how much these go for in the real world.

Good luck

Andy getting off his soap-box, cheers for reading