1985 2wd Ram...looking for new wheels/tires for it

[Rynxprs]

I'm looking to get my father some new rims/tires for Christmas. He just has black steelies on it and I'd like to get him a updated look.

Again this is a 85 2wd Ram.
It has 8 lug 16" wheels on it.

I was thinking 31's would fit with no problem. But i don't know what rims to get. Obviously 8 lug but didn't know what offset and all that good stuff.

Any help would be greatly appreciated!!!!

Thanks,
Steve