125-200cc Keihin/Mikuni cable holder/carb swap

I just got a Keihin A/S 38 to replace the Mikuni on my 08 CR 144. Searching around here I'm told to swap the curved Mikuni holder and install it on the Keihin. The issue that I'm having is that the straight holder on the Keihin cap is not threaded so I can't remove it. It seems to be a pressed together deal.

Should I find another Keihin cap that's threaded (probably off a KTM)?

Will I still need a different throttle cable?

Just curious if anyone else has ran into this issue.

Could just use a KTM cable as its a direct swap