I know this thread is old now but anyway....Got 2.5" lift, 31" Cooper STT on black 15" Mickey T on standard TJ rear door spare wheel bracket and until I can afford a new swing out bumper/spare wheel carrier (already have aftermarket bumper but unfortunately no swing out tire carrier) I had to modify the Thule spare me as my tyre/rim setup is too deep for the standard Thule brackets to fit. Had a new bracket manufactured, purchased a longer threaded bolt for the screw mechanism that holds it all together.
That was a year ago and have had no problems with the additional weight of the larger wheel/rim, Thule spare me rack and 2 MTB's, even in the really rough stuff an I use the rack at least twice a week and also on typical longer 4 week/5000km road trips in S Africa with absolutely no problems.
Image 1 - modified the square tube section of bracket - made it longer to reach deeper in to rim
Image 2 - longer threaded bolt (off the shelf) to make up addition depth of modified bracket - plastic /lock opens up to accept new longer bolt