The easiest thing to do is run taller tires. Providing your truck is original it should have an Eaton H072 rear axle. 4.11 ring and pinion sets for that axle are rare and they are not currently reproduced but they do exist. Personally I would go with a corporate 14 bolt or Dana 60 rear. It's a fairly straightforward swap, but expect to need to move the spring perches. It can be done by any reputable welding shop.
Just my $0.02