Crown stem size for Pam111?

[Timelord]

Greetings,

 

I a not sure if this is the right section to post this, but I am doing my first sterile Pam111 build with a sterile dial as no trusted dealer I know is able to get me the replica since the raids! 

Therefore   I purchased a generic case on eBay and a 6497 to fit the case!  Upon assembling it, I noticed that the interior thread on the crown is way too wide than the 0.9mm tap threaded stem on the movement!  Does anyone know or have come across  a similar situation and if so, what adapter would one use to attach crown onto the movement thread!  I do know that some thread extenders come with different end measures for different crown and stem thickness! Any input much appreciated with thanks!  🙂