They'd both have the same outer barrel with 172mm dish and they'd both look the same sitting next to each other.
The "disk" changes the thickness of the centre where it bolts to the hub, you'll need to choose based on which offset will give you the fitment you're after as well as giving brake clearance. The 18x13.5-26 R-disk will sit 1" further outwards than the 18x13.5-1 O Disk, giving a lot more room for the calipers. The R disk would extend 70mm further outward than your Enkeis.
This is 18x11-8 O Disk BBF finish (147mm dish).