There's a lot of cut-and-paste work with sheet metal, self-tapping screws, caulk, and black rattlecan paint here.
The bed cover is made of 2x4s and 3/4" plywood, attached to the truck with piano hinges. It's reasonably sturdy, but requires a great deal of effort to open.
How many miles? With a five-digit odometer, it could be 108,692 or maybe 508,592 miles. Based on the truck's appearance, it's safe to rule out 8,692 miles.
In theory, Bronco II buyers could get a diesel engine. In practice, nearly every Bronco II had a 2.8- or 2.9-liter Cologne V6, the same engine family used in the Ford Capri. This truck has a five-speed manual transmission and four-wheel drive.
Because it's in Colorado, the cab interior is plastered with stickers from cannabis dispensaries, local breweries, snowboard-supply stores, and cosmic Shakedown Street sticker vendors. We can assume that this truck saw its share of camping trips, drives to the ski slopes, and hurried repairs in Autozone parking lots.
Once the market for used compact SUVs became saturated with cheap Explorers, the value of the less civilized Bronco II crashed hard. The value of a used-up Sawzall-pickup-conversion Bronco II with a transmission that only a tiny minority of under-40 Americans are capable of operating? It's whatever scrap vehicles are selling for in your area. I don't see many Bronco IIs (or early Rangers, for that matter) in my junkyard travels these days.
The Bronco II: it's a brand-new kick!