More that I'm asking the same question. I haven't seen very many pictures with the .30 mounted. I'm currently building an RCD Staghound, and fortunately the 1:1 scale reference is in the hangar next to mine at work (outing myself a bit here...).
Bill Inglee recommended checking the Missing Lynx forums when I asked about Crusader tanks, as both they and Staghounds pre-date the era that this forum focuses on.
I hope you have some luck with this!