Nice to see all the comments

with everyone having slightly different setups every little detail changes things

Seeing Keith go with a 10" rim 305 tire and 4" backspace makes me confident that a 10" rim 275 tire and 4 1/2" backspace will work.

with the IRS when car is lifted and suspension hanging the tire will come in closer to inside of wheelwell. As mentioned it would be nice if FFR put out specs for when setup includes IRS

Bob