By the way, if the RB751 works for you in this box, the RB951 will work the same, because the external antenna in the RB751 gives nearly no improvement, this is why we removed it. It was not the best design choice, using the MMCX of the RB751 has no practical signal improvement.
Thanks. Unfortunately the RB2011 is more than twice the size and twice the price. Not sure we can use it.
We found in both the RB751U-2HnD and RB751G-2HnD the signal was poor without the external antenna. The antenna is on the outside of the metal box and the router is in the metal box, just to be clear.