have quite a bit of experience with the napco 4x4 systems... let me know what you are looking for and I might be able to help source some of the parts.
are they 17.5 split rims or 17"?? Or 17.5 regular wheels with tubes?? I always thought the .5" sizes were non-split rim varieties..
assuming your truck has 8 bolt wheels I would guess you options are 16", 16.5",17.5", 19.5"... all of these should be able to run newer tubeless tires.
