What car?
Does it matter if the spare fits in the spare tire well?
If you go staggered I would want the spare the same size as the front. I personally would rather have the one size smaller tire (if you only go one size difference) on the rear if it went flat instead of a wider spare and having...
1969 RHD BUICK GS400 CONVERTIBLE
ONE OF ONLY 1720 MADE THE CAR WAS BUILT IN FLENT TEXAS USA
THE CAR WAS IMPORTED THROUGH LOCKHART MOTORS ON THE GOLD COAST NEW FOR A LOCAL
BUSINESSWOMAN THE CAR WAS STORED FOR 20 YEARS.