Front Fenders, Hood Fit another truck

There's two ways to approach this. The easiest is to visit any salvage yard and have them look up the parts in their "Hollander" Guide. Those are huge and expensive books that will list your truck with every part, and give each of those parts a code number. Next, you look up the code number in the back of the book and it will list every model and year that part is used on.

I use the Rock Auto web site for reference for things like this. You can look up the part in question for one truck, and write down the part number from any of their multiple suppliers. Look up the same part for the other truck. If the same part number is listed, the parts will interchange. If different part numbers are listed, it doesn't necessarily mean they won't interchange. You have to figure out what is different. For example, your fenders might bolt on to the inner fenders, but the creases and body lines might not match those of the doors. There could also have been one or two bolt holes that were moved for some reason between the two years. Other than that, the fenders might be exactly the same, but that difference will warrant a totally different part number.

If they didn't tell you what is different, the parts still might work, but there's a pretty big age difference. Manufacturers make changes every year. Some are insignificant, and some seem to be just so we have to keep more parts in stock or so you have less chance of finding what you need in a salvage yard.

If the engines are the same, the exhaust manifolds are generally dictated by the body and the transmission type. One year the outlet port on one side might be at the rear of the manifold, and for another year it might be in the middle to clear a cross member or something like that. A single exhaust is usually sufficient for all but the biggest engines.