And also if it is underneath it will be incredibly loud as most of the R6 silencing is done by a collector box underneath the engine.
I think two cans and leaving the cat in place might make if fruity without being way too loud. I am going to take it to our local exhaust fabricator and see what he thinks before ebaying another R6 can. One problem is that the mounting bracket will have to be taken off and replaced on the inside of one of the R6 cans, then somehow have to be treated to look like the original matt titanium finish, might put a sticker over the mark or something. Will post again if it works, they are very light cans and with their tapered ends should look good too. Buying them off ebay is cheap as long as you go for just the can and not all the exup gubbins that you don't want anyway.