Thanks again guys.
I ended up with Hagerty because I'm 21 and they were willing to take somebody under the age of 25 if I joined my father's plan (after a lot of convincing).
They did want the truck locked up in a garage and whatnot, but it is so none of that part is an issue.
I was told to decide on a value and provide pictures to prove it and that we'd go from there. I think I have a good idea of what it's worth, I just need to make sure they agree.
Even if we can't quite agree, I'm sure it'll be better than State Farm's ludicrous $400 evaluation
I'm quite limited on mileage with Hagerty, but again, being able to get classic insurance at my age is big enough, I'll take what I can get. I don't drive the truck all that much anyway.