They look great both ways. While I was once the rare guy who ran steelies and even more rare with hubcaps, I must say now that folks have caught on to the steelies and especially with hubcaps, I'm loving the open wheel look these days. What I remember mostly until the late '70s were guys running wide black wheels with no hubcaps. The wheels were more to accommodate the wider tires than for looks. For looks, believe it or not, it was run wagon wheels. and for flash it was chrome wagon wheels or aluminum slots. Turbine wheels for 8-lugs came along a bit later. About the only time you might have seen hubcaps on wide steelies would be when they were run on the rear of a C/20... usually a camper hauler. The only reason I've been running my 8s w/o caps is because I don't have any #2 fronts and the truck is not worthy of better at this point. I feel no caps also lend to the surviving veteran look. Still looks healthy, just not as purdy as once was.
I never liked adding flashy wheels to an unrestored truck with old paint and dull trim. I had sets of period correct wheels when I bought the K/20 Highlander I had, 16.5 x 9.75 powder coated white steelies, aluminum slots, and 8.25 turbines. But I wanted a set of beach tires and 4WPW only offered 16s on a buy 3 get 4 sale back when I lifted it. I bought the cheapest wheels since I had no wide 16s and the other three sets were where my heart was. I ordered Xtremes mounted on white spokes. The consensus was everybody hated wagon wheels, pretty much still is. But they were cheap and of all the wheels available they were the only period correct style. I like to dispel popular opinion plus I felt they would lend to the surviving veteran vibe. I wanted the truck to come off as it was back in the day still. I was pleased with the look. I thought I nailed it. The first thing my friend did when I sold it to him was sell the wheels
When I first bought it, before I rebuilt the chassis, I slapped a set of 8" AR23s with 285/75s on it that I had laying around because it needed tires badly. But here is the GMC, before I rebuilt it's chassis, with the 9.75s with 33/12.50s I originally had on my Cheyenne Super Custom Camper.