Ya a 16.16 carb has a small range so if you lean it enough for a good idle it will be lean on top so puchs with performance piston port kits/cylinders and pipe hate them.
Every puch I got or worked on that had a 16.16 sha on a pp kit had cylinder damage.
On a puch Reed kit a sha (15.15 or smaller is better/has better air/fuel mix) is not so bad you can richen them up for enough gas on top and because of the reeds they still may still idle but not on a performance build PP kit.
Use a highly tunable carb on your metra kit like a phva (a 17.5 phva just rips) or phbg that has starter, idle, progressive, mid and full throttle systems so your cylinder is not starved for fuel (and oil) see link:
Set timing low or use a retarding ignition and protect with a head temp gauge
http://www.mypage.tsn.cc/rdd/TT/contents/CARB/dellorto/index.html