Look at the inner cowl under the heater on page 3.
lots-o-rust While this repair is doable, add $4k to the price of the truck for shipping and then cab corner and cowl work + other unknowns and you will wish you spent a few extra bucks for a nicer truck and had a lot less work to do. At least that is how I see it . . . I have done one really rusty cab like this and one with hardly any rust at all, I like the rust free cabs - save you a month of sundays labor!