I could not find towing data for a car that far back but I would say 2,000 pounds maximum. Try to find a owners manual. You might find one online or on Ebay.
The hitch being welded does nothing for you. I had a 94 that said it was rated for about 3500lbs. But it was a 4.3 and alot has happened between 1985 and 1994. These things arnt tow rigs, you can move a lawn trailer or maybe a small pop up camper. Anything else do so at your own risk.
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