Phil,
The issue with L.E No. 5 is an interesting question. I have a Jungle Carbine here & while i've not yet tried this on the rifle clips, I would expect it to be too short for the clip to grab. Also the butt plate with strap loop might be too wide for a regular floor block. On the other hand..........at least it has its own 'padding' on the butt
I'll test this fit later today & let you all know.
And YES, I would also like to see the dimensions you have there.