Lot of it depended on what part of the country the rigs were made. At the time manufacturers were all over the USA, and those made/sold usually stayed in the area. There were west coast manufacturers, east coast, and central.
Toyota's were the most popular, but I've seen Fords, Chevy's in our travels.
Unfortunately, they were all not the most "better built" rigs, and most I have seen have just rotted out. In our travels in 45 of the lower states, have seen many just sitting in yards, probably due to the running gear just giving out and the owners just not wanting to spend $$$ to fix.
Almost all were overloaded as they came from the factory, exceeding the GVWR. The manufacturers got around this by adding stiffer springs, shocks, dual rear wheels, but didn't help much.
The early Toyots rigs even came with a 4 cyl. engine and single rear wheel.
Would be nice to see what the manufacturers could do with a current Ranger. Would make a nice smaller class c.