My unit does ambulance corps impression and through all my research I cannot find what dress uniform a corpsman would wear. This is for parade sake, not for field duty. Since corpsmen were detached from their respective branch, regiment, company and would serve on a division level under Letterman's plan (which was a working experiment), would they wear their branch piping (ie infantry, cavalry) or medical (which would have been a staff crimson). If I had to give an educated guess on the situation I would say branch with the half chevron. If someone could point me to some literature that would spell it out for me I would greatly appreciate it.
1st OVI Co. A
Ambulance Corps Detached Service