I'm guessing the Montana registration is 1/2 the factor. Montana is #3 for the most accidents per 100k people.
https://www.nwitimes.com/autos/the-m...4071634.html#2
And NJ where you live is #1 for the highest rates on the nation.
https://www.iii.org/fact-statistic/f...auto-insurance
I have Midwest Classic as well but underwritten by Infinity. Stated value was not an issue and runs approx $380 a year here in TX.