Tom coe look at the wheel see the large nuts on the outer ends ot the spokes? those are your lug nuts. If you look there should be some wedges between the wheel and the spoke. The inner edge of the wheel will have a raised area which the wedge seats against tho apply pressure to hold it in place. Back the lug nuts off and per stone cutters suggestion tap wedges with hammer then remove lugnuts the rest of the way. (Ignore the smaller bolts near the center of the hub for the time being) Once you have removed lug nuts and wedges the outer wheel should come off. After you have the outer wheel off there should be a spacer about 5 to 6"wide approximatley. It should have a lip you can tap against to drive it off the spokes. Now you are to the inner wheel it is the same wheel as on the outer except it is turned in the oppisite direction, the raised edge is turne outward so that it wedges against the wedgelike raised edge of the inner side of the spoke normally you can just start wiggling the wheel back and forth and it will slide off. You than can study the spokes and see if they are adapters or if they are part of the hub. On the front wheels they are mounted with the raised edge to the outside and flat edge inside with a slightly different type of wedge and lugnut will likely be the same size as rear. Don't know if I've confused things further but print this out and sit down by the truck with the beverage of your choice and study it few minutes and I think it will get a little clearer good luck

1938 1.5-Ton Chevy
1948 2-Ton Chevy

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