You will need to make a shim out of 1MM thickness stock. I used copper sheet because it's what I had on hand. Some have used milk jug plastic. The puch intake is 20MM OD and the Dellorto clone carb without it's crappy shim is 22MM ID. A Viton O ring would best be used to complete the seal. Then file the mounting holes in the intake and either make a Pergo flooring spacer to bolt it to the cylinder or just grind off the edges to fit with a gasket. If you can, the Pergo flooring spacer is sweet!
A 62 or so jet would be a good place to start. I think an unlabeled 68 comes with that carb. It will be too rich.