18's with 275s on a Duster

I do have a b body housing laying here I could just order some axles and be set with no issues.

I just for got about the lip like you stated above as well

What year B-body housing? A 68-70 with a 1/2” spring offset would basically make a 18x9 +35mm a perfect wheel. And since you’d have to move the spring perches on a B-body housing it’s the perfect time to install a 1/2” spring offset.