Sorry for yuor loss. Most dads are not that noticeable until they are gone. It's the way a good dad is in my book. We pick up the tab, keeps things moving and cheer silently form the sidelines.
I lost my dad a little over 6 years ago. Ache is the same. I am just more used to it. On of my favorite memries was a camping trip we took with my parents. my wife and 4 boys. The kids wer finding money all over the campsite. They spent a lot of time amusing themselse between exploring the stream and countnig their new found riches. I made the comment to my mother about somebody losing a lot of money. She just said, "It's you father" He would drop his spare change and then just watch the boys search for it. Over the course of a week, they probably spent a few hours looking for coins.
It seems that since he died, whenever I am having a particularily rough day at home, at work or on the road, I always seem to spot a penny or some other coin laying on the ground. Hey, you never know.
He will always be keeping an eye on you.