Hi folks - cheers for the replies - apologies for the delay in getting back but I'm in the UK so time difference and all that.
I've got no proper knowledge about the GAR markers other than they appear to be a star on a spike - did they stay in the graves all the time, did family members keep them, did people steal them??? The card in the link does appear to be referring to some sort of upright marker and can't be referring to his actual headstone which is flat. I manage a few findagrave memorials for the whole family which are linked and here is Patrick's:
https://www.findagrave.com/memorial/60738711/patrick-f_-o_neilThere's no marker present but I'm convinced it must have been GAR and that F. Company, St Vincent's Roster is to do with him being a member of the GAR and that ultimately if any records exist for this they will lead me to an actual regiment.
I've gone through to the best of my ability, not being an expert as to the minute details of battle formations, army groups, etc, etc as much online info as I could find and if I remember correctly (I haven't got my notes in front of me) there were less than 10 NY regiments in total involved. I've got pdfs of the rosters for every NY regiment - infantry, calvary and artillery and I went through them for Patricks and there wasn't anything close in age. He would have been 17 in 1861, 18 in 1862 so no need to lie about his age and plenty of ages given as a lot older. Others either died, deserted or were POWs by the time of the Nashville campaigns - in short no likely candidates.
I have sometimes explored the idea that the obit is made up as far as civil war service was concerned. It's certainly wrong in that only one brother perished plus it was written by his brother Michael who at this time was a leading commercial dignitary in Akron and he would have been flattering about his brother. He would definitely have known that only one of his brothers died. There were 6 brothers in total. Peter (1836-1882), Felix (1839-1880), John (1842-1862), Patrick (1844-1918), James (1846-1906) and Michael (1850-1927). Peter is the most likely other brother to serve (if the info is correct) and he appears twice in the NYC drafts. Felix appears to have paid a substitute and is listed in all the NYC directories during the Civil War. His obit says he was in Company I of the 12th Regiment N.G.S.N.Y. Dowley's History and Honorary Roll (1869) lists him as a Corporal of I Company with date of warrant given as 27-08-1867. This date is post Civil War and I can't find any evidence he served during 1861-1865 in any of the muster rolls - I did find some short term ones for this regiment. James and Michael were too young and never served.
Maybe Patrick himself faked a history about himself after arriving in Akron either about his service if at at all, or hiding a record of desertion or similar, either with Michael's collusion or not? This might explain his absence from the 1890 Vets Schedule? Surely though if he had then he would soon have been caught out by other vets? Anyhow that's a totally different and very cynical set of thoughts.
So it's GAR???