2002 de-duallied wheel offset question

[fifty]

I have a 2002 F-350 dually...that I deduallied...It still has the big old axle out back...with 2 inch spacers up front to equal everything out...

I am currently running factory 16x6 f350/excursion rims...

Problem is the stick out...a bit... I would like to go 18x9's or 20x9/10's. What offset should I go with to suck them in a bit...

I really like the method racing mr301's but they only offer the 18x9 in 4.75 bs:

Size: 18 x 9
Offset (mm): -12mm
B. S. (in): 4.75"
Bolt Pattern: 8 x 170mm
Hub Bore (mm): 5.150"

and the 20x9:

Size: 20 x 9
Offset (mm): +18mm
B. S. (in): 5.25"
Bolt Pattern: 8 x 170mm
Hub Bore (mm): 5.150"

and 20x10:

Size: 20 x 10
Offset (mm): -24mm
B. S. (in): 4.50"
Bolt Pattern: 8 x 170mm
Hub Bore (mm): 5.150"

So does this mean my only option for sucking the wheel back in is to go with the 20x9 wheel?

Attached is a horrible picture of the rear tire sticking out. This is a 265/75/16 BFG AT KO, thats well worn... Fronts are the same (for sticking out)