Just a quick observation. If you were to flip the tire over is it possible the studs will be long enough? Or is it deeper on that side?
No, the clamping pressure is from the frame through the rubber to the bottom plate. The tire carrier in the middle has two plates that help keep the rim centered on the bar.
Here are some pics that show where things were added. Still need to tighten it up, tack weld and throw a lock on it but it is fine for plunking around town.
here is the passenger side. For this size tire cutting 2" off of each threaded portion would be ideal before adding coupler (making sure to center old and new threads in coupler til they touch
This shows how close it is to the frame. Pretty close, would not be able to fit much bigger and due to decreased clearance wouldnt want to fit much fatter either.
Here is driver side again for this width tire 2" would be optimal removal on threads before adding coupler. Coupler is used as the adjusting stop to achieve proper tension on things and nut above frame locks it in place.
Since this is a 33 I would say a 34 or 35 may be able to fit but I would keep it skinny. Oh and to do anything larger than 33 it appears you would need to bend the hanger bolts to a bow to accomodate the additional size. The bolts were pretty much touching my tire.
Good luck and have fun lifting your tires up there! It's..."fun"