Your best bet is to dual screen the build and price or order guides. They have many of the same features, just different variations of them. Also, if you do inventory search, you can see the dealer orders and how the price stacks with options. Navigator does have some exclusive features, but your mainly paying for the material and build of the vehicle. A good way to think about the pricing and model comparison is this:
Expy max starts at 72k and is pretty much fully loaded. Though fully loaded, some things arent available in the expy thats in the navi like lthr all three rows, the heads up dis unit, sec row console(w/ sunroof ctrl), and the lincoln concierge service.
The navi reserve starts at 74k and it excludes heated and cooled seats, sunroof, drivers assist pkg, 30 way massage seats, ccd, 360 camera etc. Even steeping up to the select model is still missing those features std except the ccd(thats right, cooled seats is an option even on the select). The above features are std on reserve model, but they come with a 86k price tag.
Honestly, if your even considering an expy the plat is outfitted like a luxury vehicle. You can load up a limited model and save yourself 5 or 6k if your judicious with the options. If you rele dont want the trucky interior look the navi select is very much the value as you can option it with all available features, though the price will reflect this. The interior alone is worth the upgrade though. Hope that information helps