I have rims with that backspacing and I know I will not be able to run any bigger that 31" without doing a 2"BL.

The 3" SL lift alone will not give your tires that much more clearance, as it simply raise the suspension components.

Consider doing the 2" BL anyway to improve articulation (flex). Most people still running IFS have 3"SL & 2"BL.

OR...get new rims, BS of 4.75 and have tire rack remount the tires.

OR...get a sawzall and a grinder!!!