A good welding shop can build you one. If I had the dimensions or yours I could build it, but I don't know where your from. I am a certified welder and have a shop.
Im in nj. I am currently working with cat on trying to procure the blueprint or I may just have to fabricate it out of regular exhaust tubing and machine a bushing to connect it to the turbo.
I wouldn't use that thin exhaust pipe. Go to a plumbing supply store and buy a weld type 90 degree elbow. They use them for gas lines and such. They already have a bevel built into them for welding and no threads. Buy you a short piece of schedule 40 steel pipe the right size for your muffler to fit over while your there. 3 1/2" schedule 40 is 4" on the outside. Torch/plasma you out a flange and drill your holes to match the one you have and start welding.
Got the blue print today. Seems easy to make except for the whole 4" to 5.30" tapered elbow bit.
Hi Powersmoke, what's the process for obtaining blueprints? Do you go through the dealer or do you contact head office?