I have a neighbor who is handy with a welder. He installed the "flat flange" on the header end of the cat. JBA likes to do it that way, but I think you are better off with Thorley's method of just welding the cat to the header (leaks can be a PIA at that flat flange interface).
With the long resonator Solo includes with their V6 high flow cat, I found it very easy to cut the stock mid-pipe back (the Solo cat and resonator are a bit longer than the stock) and when you've got the length right, just use the OE sleeve clamp (doesn't have to be perfect- those clamps are great!)
Because of the angle of the Solo design, for everything to line up, you will lose a little ground clearance (1" max). I trimmed a couple inches off the end of the Solo resonator and about the same for the stock midpipe. I never had any issues with touching down on anything going up driveways, etc.. I think the placement just behind the front tires raises everything up, increasing your clearance right when you need it.
Also never had a CEL (Solo provides O2 sensor extensions that work- period) and never required any tune- the car ran like a scalded dog! Those ECM are able to adapt to significant airflow increases.
So thanks to my neighbor, this was a DIY project that worked like a charm. Combined with Borla's Touring axle back mufflers (#11776 I believe) it sounded great too IMHO.
Any other questions, just ask or drop me PM.
