Quoted from John_in_NC:Still round.
I suppose a rollover can be any shape you imagine if you use proximity sensors ala TOM
You can have it be round and still index the top of it. A keyway slot would do just that. Should have been done like that in the first place probably, but now you have what you have. A circular rollover that is indexed would allow for a decal on top and then the space where the decal's image used to be is freed up.