Rear diffuser installation

[RandallNeighbour]

Has anyone here installed aftermarket rear diffusers from eBay that sell for a couple of hundred bucks?

I jacked up my car and tried to install them after I got them and I'd barely get one bolt in the top (far too close to the muffler) and then I could not get any of the other bolts in place... it looks like the bolt receptacles in the diffusers are not placed in the right places.

I drilled a hole in the bumper where I thought one was off, and then had a look at it and I don't think they're placed properly.

The eBay listing said removing the bumper was highly recommended. Now I see why!

Anyone have any pictures of how to remove the back bumper?