Borla rear diffuser adapt to fit?
 

I just noticed... the Borla diffuser mounting brackets are all separate.

Has anyone tries to mount this to a non-borla exhaust? Looks like it's certainly possible. Just some different mounting holes need to be drilled. I like this as it's much more low profile than other available options, and allows retaining the stock diffuser trim.

Question is how effective it would actually be....

http://www.carid.com/images/borla/diffusers/77012.jpg

It definitely helps with the borla catback. Without it the ass end of the car is way too squirrely. I went without it for a few months and when I put it on there was a very noticeable difference.

Let me ask, did you see the one for sale and that's why you are asking? I was debating doing the same thing, haha. I'm sure with a reasonable amount of effort you could make some adapters to fit it to the car.

Nope. I was just looking for alternatives to the cleib diffuser (whcih can't be bent/adjusted if it doesn't clear my exhaust, and the speed factory one which sticks out too much for my tastes. I just want an underside that's as flat as possible...

If I could pick one up for cheap I would definitely give it a shot myself. Might be a little bit of a project making some new mounting hardware, but that doesn't seem so hard. I'd probably add some extensions so it went further under the car to fill in more space.