Tony, as always I appreciate your input and help here. As a follow up I took the SSX and YBX cans and blew them apart and put them on a bench to evaluate the differences.
To answer my own question the YBX will never flow as much as the SSX even if modified because the diameter of the header pipe coming off of the cylinder is smaller and a choking point that can’t be overcome on the YBX.
That said…I still drilled out the holes on the YBX in a similar pattern to the SSX on the inside, put a few more holes in the cap and put it all back together and it’s going to work just fine with the WB3A big carb I put on her motor to give her the power needed to keep up with me and have a little fun.
Had I not been bored with nothing better to do a $40 used SSX can would have still been the better option in my opinion but my fix will work out for her since it’s just for fun.