The outlet pipe of the stock exhaust from the turbocharger does not clear the engine mount structure. Sonex sent a blank (no exhaust pipe) flange in order to weld an exhaust pipe that would clear the engine mount tubing.
I found that the blank flange thickness would provide just enough spacing to enable the stock flange & pipe to clear the engine mounts.
In fitting the flange stack, one of the holes on the blank flange required drilling oversize to 3/8". Drilled with a cobalt drill bit with Boelube as a HSS bit simply overheated in the stainless.
Stacked the blank turbocharger exhaust flange and exhaust flange with pipe to turbocharger. Used 5/16" x 1.25" exhaust bolts from JEGS. Will likely replace a bolt with a stud in order to hang the stack during assembly.