I’ve seen people tow these things at crazy angles, so I wouldn’t assume that just because it “worked” with an F350 means it will be right with yours.
Does it have the OEM standard suspension, the OEM 3” raised suspension, or something else modified by a previous owner?
If it has either stock suspension a call to
Scamp will tell you what bedrail heights will work. If it’s been modified, you’ll want to know the actual height of the loft with the trailer sitting level on level ground.
As said though, even if it doesn’t fit your truck, that can be fixed with a new
axle, which it may well need anyway given the age. Torsion axles have a typical lifespan of around 20 years. If the price and condition are otherwise right...