The Lock N Roll Articulating Channel Tongue Trailer Coupler # 336TS528 that you referenced is designed to fit on 2 inch wide frame channel. If you need a version that fits a 3 inch channel you'd want the part # 336TS508 instead. The 3 inch channel width is the most common size seen on trailers so this would be most likely your best option. The distance from the bolt center to the top of the channel is 3/4 inches.
On the vehicle side you'd then need the # 336VS501 which fits a 2 inch trailer... view full answer...
Hey Sean, thanks for the picture! That's a cool car. The Thule SquareBar Evo Roof Rack for Rain Gutters item # TH52VA is indeed compatible with your 1980 Ford Pinto. It attaches directly to the rain gutters so it'll work with both the 2-door and wagon models.
The Thule item # TH52VA roof rack has a listed capacity of 220 lbs, but I recommend double checking your Pinto's roof is rated for that much weight. The square bars measure 47" long x 1-1/4" wide x 7/8" tall so it is compatible with... view full answer...