Josh,
sorry I forgot, this weekend I'll dl the RLTC settings and send it to you.
Assuming you have no fender mods, with this specific sizing/offset trying to step up even one tire size from your 245/40 to a 255/35 front is a VERY close call. For example, if you had +40 offset, I agree with what the fitment guide shows which is that it would fit. So that means that with your +37 offset and a 255/35 tire, the difference is that the outer tire edge sticks out by an additional 0.12 inches over the +40. That's so close that I could not say for sure and I think the fitment guide even takes exception to that close of a fit.
Is it possible you can have a 255/35 mounted to see if it fits? Otherwise I wouldn't take a chance and stay with the 245.