UnkleRuckus -- Welcome to the prestigious and exclusive brotherhood of 3800 owners! (It's actually neither but what the heck ...) Ditto to what Elderly Iron says. I've had pretty good luck with my local NAPA (Guy Auto Parts in Clement, MD). Find the M&P NAPA or other such parts house near you the pros use.
Also, check out our Links section (see the menu at the top of the page). Some vendors (like Jim Carter's Antique Truck Parts, Kanter, American Classic, etc) carry 1-ton parts.
Several folks here are actively working on Advance Design duallie 1-tons and will hopefully chime in soon ...
The good news is that the parts you seek are available.
The bad news is that they are harder to find than 1/2-ton parts and when you do find them, they will be more expensive.
Other than that, Mrs. Lincoln, the rest of the show ought to be pretty good.
John
