No Solid Proof!!!!
Jeezzzz, Check out neutral sources you will find the shiva Idol, The Bull, The stone inscribed words of Shiva and Shambhu..etc; etc; etc;
Good lord, m sitting in my office and doing some important work, otherwise would have given you so many references..
I was talking in general not point towards your ancestors in particular.
I like it that you respect your ancestors, if you really do, respect there religion as well.
Remeber Allah says in glorious Quran- Only He is the judge who can decide whether You are a muslim or not.