The D50/Arrow pickup was introduced to the US market in 1978. It was 2 wheel drive only.Dodge did convert about 4000 a year into 4 wheel drive.
In 1980 a 4wheel drive version was made by Mitsubishi. These were still sold under the dodge moniker. Mitsubishi did not start selling cars in the US under their own brand name until 1982.
I am not sure what the differance in hubs are with the pre 82 versus the latter years.
And yes my 79 Arrow has Warn hubs on the Dana 30 axle.

Well on my way to becoming that eccentric old man in every town.(crazy as a s#@thouse rat) With a yard full of desireable old vehicles that tells you, Sorry they're not for sale..... Someday I'm going to fix them.