First, the electronic tool allows fine tuning exactly what is desired and changing as per conditions may warrant. First of all, you don't NEED the larger tires in the first place. Go with any number of E range 31.5" tires and you'll be perfectly fine for years. No rubbing and room to spare for a snow chain depending on the style (more on that later if desired)
By simply wanting the Duratrac and it's limited sizing, you are stuffing yourself into an area with compromises such as lower load range (fine for general uses) or too large for factory clearances.
For what it sounds like you'll be doing, even the current BFG AT Ko is perfect and in a perfect size requiring none of the above complications. Consider how awesome it would be to have room left for a snow chain? The Duratrac in 275/65x18 will NOT allow that. Furthermore, the rod mod or even the IIDtool are not the end of that equation. Ideally you would also have the fender liner altered in the rear and the steel cut back in the front for TRUE clearance. These are areas that WILL come in contact regardless of the rods or permanent lift. This is because the moment you compress the suspension into the wheel well, or make a 70% lock turn, the larger tire will rub without the alterations.
So, want to enter the rabbit hole or keep it simple, reliable, and also cheaper. Going above 31.5" is a committed path involving more changes than most people will actually utilize often enough to be 100% necessary.
Did you know that you can induce a higher factory lift mode by simply faking it being grounded? Just place a jack stand under the sill or jacking point, lower onto it, as if it were a log/stump, and you'll see the computer think it needs to raise itself into "super extended" height not available just by pressing the levers. Driving too fast in this mode will cause it to lower, but you shouldn't be driving faster than that anyway at such height as there is nearly zero suspension down travel remaining.
Keep in mind, there are limits with this suspension such that when the height is maxed out, the traction usually available by keeping all 4 tires touching will be lost if not on level ground.
So, rods give you no options to role any differently unless you want to get in there swapping them out all the time... not me, annoying and just ads more chance to damaging the delicate parts it mounts to. Larger tires than 31.5" only work well if in conjunction with other alterations to the vehicle for clearance purposes.
Just get some version of a 265/65x18 and you'll really just not need to think about this again for 60,000 miles.
About the chains, a true wrap around chain will require more clearance such that it would fit on stock wheel if tire were narrower than the 265 or it will fit on a 265/65x18 with spacers behind stock wheel. When adding spacers though, the turning clearance will come up tight at full lock.
Rear wheel well clearance will be an issue if you were trying to trail ride using the chains with articulation going on but on forest roads or the highway in deep snow, it would be pretty much flat all the time anyway.
There are some types of snow traction devices which do not wrap behind the tire such that you could not need spacers. These are generally easier to put on but are also just for roadways, not offroad.
Being in Colorado, you should look into one of Bill Burkes outings during winter.
