When Red Chili 1 was clipped by a Furd Exploder running a red, I ran into the same thing. They just wanted to pay book.
Since a Cruiser has no accurate book these days, your strategy should be a good one. I nearly doubled what I got via these easy steps:
1) Be persistent and polite. Tell them their offer is simply not fair value. Ask them what kind of supporting data they need. By the way, they won't pay labor for mods. But they will pay for supportable retail prices - depreciated, unfortunately.
2) Call often. Provide comparables for sale at or about the price you think is fair (really, shoot high: they will still dicker down).
3) Did I say be persistent? And keep providing comparables?
4) If you don't get what you want ask to speak to their adjuster's boss. Start over with him/her.
5) Call often and be persistent. Remain nice, but wear their phone out. Keep providing comparables and additional information.
6) Repeat as needed.
Finally wore the State Farm guy (you know, the worst possible insurance company for such things) down until he, in desperation, gave me an almost fair price, AND a stealing deal on buy back (they have a fair amount of flexibility on that, so it can be a bone they can throw you).
To avoid ever having to do this again, I got an enthusiast's/collector's stated-value policy on Red Chili II. Not real expensive, a very good idea though.
Heb Dduw, heb ddim; Duw a digon
I'm that gun-totin', farm-raised, evangelical, pro-environment, OHV ridin'/drivin', Southern civil rights pro-labor Liberal yo' momma told you couldn't possibly exist.