canadian carrier mk1 gun rest

[Lynn Eades]

I think I have all the rubber rests but not the angle iron for all of them. They are made from 2 x 1/8 (50 x 3mm is the available size,here)
Are they all mounted on the outside or inside of the hull or is it a mix?
As a note, i think all the U.C.s that came here were early and had rubber rests. never seen a wooden one here.
The other thing I have trouble with is the high and low ones.Were the high ones from British carriers and the low ones for Canadian carriers. Michael R. has told me there are both in Canada. I wondered if the high ones might have been made for British contract carriers? Any thoughts or answers?