MAN, I can't believe it! I wouldn't ever expected to find somebody using that combination, especially with a 15mm Dell'Orto!
Is it an SHA model right? Only SHAs has the 15/15 nomenclature, whereas PHBGs has only one number; I do believe:
That 15/15 has a considerably larger airflow than the stock carburetor or the NT carb, it must be a very responsive engine!
I required to know the spacing between the carburetor studs, I'm aware which the right stud is approximately 3 degrees lower than the left one, using the middle of the interaxis as reference; I took the opportunity to ask because we are in the thematics, despite I could take the carb off myself: The house and the parents are taking away all of my freetime, and for my dearly sanity, I'd better not go fiddle in the garage this weekend.