i would recommend a 1ton SRW ExtCab for your purposes. By far enough for these campers. A 3/4 ton is very close to it´s (paperwork) limitson a longer trip.
A DRW would provide more payload but on bad and narrow roads a DRW can catch bigger stones between the tires and dmage them. Also it is much easier to handle a SRW on narro south american mountain passes…only my few cents…
2000 F-250 SuperDuty SC Lariat Longbed 7.3 ltr. 4x4
1992 Jayco-Sportster 8ft Popup - rebuilt 2014/2015
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