the pricing is all over the place for a reason; a clean stock MJ in LA is valued differently by the locals than a clean stock MJ in New Jersey would be. and a heavily modded MJ is different than an MJ pulled out of the woods after 20 years of sitting.
For selling purposes the value of a particular truck will always be the compromise between buyer and seller and the market they are in. the value will usually be compared to the other local trucks for sale.
For insurance purposes, it's all about MJs near you that are in similar condition to yours that are currently for sale. This can include more trucks than the selling scenario since a buyer might have very particular tastes (needs an automatic for example)
I added in the rest of the models to the original post. those names only kinda mean something since back in the day you could add a lot of things to a base model to deck it out like a higher end model. My base model 86 had the big engine, 4wd, AC, metric ton and some other valuable perks. still a base though.