I've given thought to the lever latch issue several times after receiving my Pietta 5.5" barrel 1858. It's of recent manufacture and also has the non-dovetailed latch. I thought about rdstrain's suggestion of heating the barrel and latch it to see if she'd break free, but not knowing if it's tapped/threaded, or soldered, or just pain press-fit in place gave me cause to second guess the plan. My biggest concerns were ruining the temper or bluing of the barrel, and boogering the re-installation.
My reason for wanting to take out the cylinder pin is two-fold. First is to aid a thorough cleaning because I'm a fanatic like that.
Second was my plan to turn several small grooves along the length of the pin to hold more grease, hopefully extending my range sessions before lock up from excessive fouling.
I've come up with a theoretical solution that I have yet to work up the gumption for - cut the cylinder pin in twain and build a hinged pin such as shown in the pictures posted by Smokin_Gun. Were I to work up the cajones to take my beautiful Remmy under the knife, these are the steps I would follow:
1) Apply painters or masking tape to the bottom of the barrel from frame to latch so as to prevent accidental scratching.
2) Slide the cylinder pin as far out as it would extend to the muzzle
3) Slip the thinnest sheet of steel I could find between barrel and cylinder pin to prevent gouging the barrel
4) Cut the latch with the thinnest/finest hacksaw I could acquire (to minimize shortening the pin unnecessarily)
5) Cut the pin in such a location that it would be located within the frame if fully inserted - not within the cylinder!
6) Make a hinged pin out of the 2 pieces as shown in the pictures by Smokin_Gun.
Sadly, this will not satisfy pbower's requirement, because the ejection assembly has an integrated cylinder pin with the same length as the un-modified stock pin. Which leads him back to figuring out removal and re-installation of the current latch, or removing the barrel to install the ejector - because I don't think anyone would try a hinged pin on the ejector itself, seeing as how they are so darned expensive!