A couple pics, sorry for the potato quality.
The 10.5" is on an SBR lower. You can see the magazine cut visible where I removed the ribs; I need to cover that on that mag. On the shorter mags as shown in the 16" carbine, the cut stops at the bottom of the lower's magwell opening, so the cut is not exposed while the mag is in the gun. Probably not ideal for really dirty environments, but it works well for normal wandering around in the woods.

[Linked Image]
[Linked Image]