Hi there - I'm hoping someone might be able to help me!

My great grandfather, John Markovich was born overseas but spent most of his life in Buffalo, NY, before moving to FL with his second wife. His social security death index says he died 1 Apr 1966 in Hillsborough. I haven't been able to find an obit or death notice. I know that in Buffalo, I can go to the library and search the death index to find information and then request a copy from vital records . Is there anyone that might be able to assist me in finding more information on his death? That is the only information I have - sorry - I know he remarried a woman named Thurley/Thurly but that could have been a nick name. Haven't been able to track down that marriage license because she is a huge unknown and NYS has strict privacy laws.

Thanks so much!