I was able to install a Kirst 1858 ejector on a 5.5" NMA. I worked out a work around for the cylinder pin being too long on the 5.5".
1) Cut the old cylinder pin out. Pretty much it was like Caesar crossing the Rubicon. Once you cut out the old pin, you are done with percussion cylinder, unless you use it with an ejector/cylinder pin that is modified. I will get another cylinder pin and modify it so I can use percussion still.
2) trim the breech end of the ejector/cylinder pin about to make it about 1/8" shorter, that leaves 1/8" left past the end of the cylinder to engage the recoil shield for stability.
3) trim of 1/3 the width of the loading lever latch on the barrel, on the side the ejector is on. That still leaves 2/3 the width to engage the loading lever catch.
4) cut a square notch the T lug on the side opposite the ejector, about 3/16" x 3/16". This allows the cylinder pin/ejector room to clear the now trimmed lug. It still allows enough forward surface on the T lug to be held in place in the notch in the front of the frame, by the rear edge of the rammer arm.
Works perfect and REALLY looks cool on the 5.5 inch!
Pics to come when I get back in town at the end of the week. I am gone until Thursday or Friday. When I get back, I will install the gated conversion on the 5.5" too. That will give me a 5.5" and an 8" NMA, both with gated Konverters and ejector rods.
I am going to give Walt a written and photo directions so he can have it on the web page. This will work with either the Tuolumne Lawman transitional ejectors (that I am working on for Walt) or the upcoming future production ones.