Grandpas DNA can't be tracked the way grandma's can.
A portion of the mothers DNA gets passed down unchanged.

Since momma grandma married 3 times I Guess I have 7 grandpas.
I wish I had stories about grandpas but I only met 2 which were of no relation. All I have are vague outlines consisting of jobs they had.

I have no knowledge at all of my biological dad's dad. But I bet I could find out. All I know is my dad's aunt was Gene Hackman's mom which must mean that I share one of Gene's grandpas.

One managed the VFW that was so thick with cigarette smoke you could not see the far wall. He got emphasema.
One got to fly WWI airplanes but froze his lungs and was grounded. Later he went to Chicago and worked for Sears as a graphic artist for their catalog.
On my step father's side grandpa was a tinsmith in Boston and made pots, chests and anything else made of metal. He liked to tell of fixing Babe Ruth's fenders, which were frequently dented. He learned to read English, unlike gramdma who read only Yiddish papers or a little bit of German, Polish or Russian.

The Mormon church is supposed to have one of the most extensive geneology libraries in the country. Its reason e'etre may be founded on racism but I hear it is accurate.
Then there are all sorts of pay as you go geneology websites that I don;t trust as far as I can throw them.

Who do you trust for geneology data?