Hello all,
As you may know (or not) I am not one of the proud owners of a M65-A keyboard.
This means that everything that I did was based on dimensions I could find open source on the M65-A plate and PCB.
That also meant that I could not test the plates and PCBs myself and had to find a nice person from this community to do it for me.
And @pixelpusher accepted to help me on that task 
His precious feedbacks have been done very early during the design phase and he also did a lot of measurements for me on his own board.
He recently received a Type S PCB, a full plate and a half plate and quickly began test fitting the plates and PCB.
The plates, like the PCB, will definitely need a second revision. They work but there is RGB light bleeding from the top and bottom part of the plate; this was somehow present also with the original plate but less obvious, while I’ll not be able to completely eliminate the problem I think I can safely mitigate it.
And there was some unknown details (not in the official open source plate version) that forced him to do a bit of sanding.
Apart from that, good news, it looks like the Mini USB connector is spot on 
Now his own M65-A PCB lives again
Thanks again @pixelpusher for your help !