Because these discussions are a search for knowledge and Facts by sharing what we each know, let me make a contribution. The "short" Schenkl 3.67" percussion shell was used by the Yankees at the battle of Spotsylvania Court House. I'm certain about that because I dug several fragments from one there, having the distinctive large raised ribs and long fat tail-knob with rounded edge.
Carl, I checked with Bill Graham to answer your question. The Confederate magazine at High Bridge VA held a number of 3.4/3.5" (dual-caliber) Read shells, made for use in the 3.4" Virginia Reamed-&-Rifled 4-pounder Smoothbore and 3.5" Blakely Rifle. It also held some of the late-war "bluntnosed" 3.67" Read shells, for a 20-pdr. Parrott Rifle.
Regards,
Pete