OK, you can't miss the diaphragm valve, it's on the top, and it feeds down into the top of the bore. If it's there, and you don't blank it off, your carb will suck air in and screw up your jetting.
As I understand it the Casa kit is not tuned to any degree, so the jets you've got may well sort it,
if they are decent quality jets. Try them but, if you start having problems, and think they may not be bored right, get proper Keihin jets and needles. ScootRS jets look a bit scabby, dull brass, poorly stamped numbers etc. Keihin ones are miles better and you
know that their JJF will be leaner at 1/4 than the JJH, as it should be.
Anyway, try what you've got first before you start buying other stuff. In the absence of anyone else who'll come on here with personal experience of this carb and this kit, personally, I'd start with the 108 main, 34 pilot, JJH needle clip 2nd from top. In the UK I set my float at either 21 or 22mm, and make sure your choke is working properly. If you're going to stick up a photo on this site, I'd be interested to see the new ( I think) ScootRS choke mechanism, because the old ones weren't up to the job, at all.
If you haven't set a Mikuni or Keihin type carb before, print off the ScootRS tech pages, and the SCK catalogue, as these will be a great help to get your head round them.
Power jet. Yes, you can retro fit them but you won't need it with a Casa kit and a Clubman. Let us know how you get on, and good luck
