Does anyone know the proper dimensions of the optics side plate on an AK?

I bought the Midwest Industries 30mm side mount with hopes of mounting up an Aimpoint pro on my AK74, but the mount seems super loose. From what I see online, those things are supposed to slide on from the back and tighten in place with the cam system, however, the mount has so much clearance on my rifle that its can be placed directly on, like a pic rail. I was still able to secure it by tightening the cam system, but it digs into my top cover, doesn't co-witness, and gives me no faith it will maintain zero.

Now I'm left wondering if its my rifle or the mount. Height of the rifle's side plate, from tip to tip, measures a hair short of 14mm I tried google to find specs on the AK side plate to no avail.

Thanks