M5 exhaust on a 540
Can it be done? yes? do you really want it done? that's up to you. do you REALLY feel like HAMMERING (note the capitalization) your FULL tire well a bit to wedge the passenger side in? or you can just cut it and invert the cut part so you'd end up with a pretty, yet wedged, spare tire well.
Can you OEM spare tire still fit? yeah, i suppose. where it would normally sit? never seen it but something tells me the answer is no, not really. it could be just a centimeter (yeah, gotta conform with the world guys, sorry USA'ers) off to the left (hey, i'm a righty OK!) but nothing detrimental.
It takes a lot of work to be lazy.