I cannot answer the direct question about wearing Masonic insignia on the uniform. But, in my research on guerrilla warfare in Civil War Missouri I have encountered at least three instances in that tragic "no quarter" warfare fought there between the partisan rangers or guerrillas and Union regulars or militia where a person on one side displayed the Masonic sign of distress and was spared from field execution by a member (usually an officer) of the opposing side.

I documented one such instance on page 99 in my 2007 "Guerrilla Warfare in Civil War Missouri, vol. II, 1863," published by McFarlanrd and Company. This took place 26 May 1863 near Nevada, county seat of Vernon County. I recall that the source was an 1880s-era county history. I am not sure offhand of the documentation of the other incidents, but it seems to me that I read of them, too, in material written in the late 1800s.

I hope that helps.

Bruce Nichols