Moving fifth-wheel aft of axle centerline on single axle?

Looking at buying a new 389 Pete single axle tractor. Not a lot of these units out there. A couple that I am considering have fifth-wheel that puts center of kingpin right at center of drive axle when slid all the way back. I would still need 2-3 more inches of clearance. Dealer is offering to move fifth-wheel track back a little to facilitate the needed clearance. Track is not huck-bolted. My question is, would having kingpin center 2-3” aft of single drive axle center be ok? Would it be a huge “no-no”? Anyone know?

 

Clearance issue is from kingpin to back of sleeper. Hauling large vans that overhang front of trailer.

 

I was thinking that because downward force is spread out a little by stanchion of fifth wheel brackets and axle is 4-5” in diameter, the downward force is still kind of stacked over supporting column so how much leverage could really come into play?

 

Stinger car hauler has fifth wheel several feet behind drives?? Not being argumentative, just saying?