VF 101 Framecounter doesn't work, how to get the top of??

[Belgium]

Hello you guys,

I just recieved my black VF 101.
It's not in mint condition but everything seems to work wel.
Except that the framecounter isn'working.
I tried it with a real film.
Does anyone lnow how to get the top of?
The three little screws are already out, but the windlever gives some resistance.
Any help please, I dont want to break the little heavyweight marvel 🙂

Thanks a lot,
Thierry