Does anybody know the name of this movie?

Hi everbody.

I am a newbie at this forum, and this is my first post, so please be gentle... ;-)

When I was but a young lad, way back when dinosaurs ruled the Earth I saw a Kung Fu-flick on video.
Back then I thought it was great, but I forgot all about it in time. A couple of months ago me and some friends were talking about movies we´d liked when we were younger and I suddenly remebered this one.
The only problem is that I can´t remeber the title of the bloody thing.
My recollections of the plot are somewhat hazy, but as I recall the hero was learning Kung-Fu to avenge something or another.
The bad guy was a master of the "deadly finger styles" so the hero searched out masters who could teach him the various styles (index-finger style, ring-finger style and so on).
However he is unable to beat the "Evil One" until he learns the deadly "thumb-style", which he uses to dispatch the aforementioned enemy.
The movie ends rather gorily with the hero poking out the "Evil One´s" right eye and then shoving his thumb into his heart.
This was an old-school movie from the late seventies early eighties.
If anybody remebers the movie´s name, then please help a frustrated moviefan..

My first post and I can´t even spell remember correctly.
****, ****, ****...

And of course it is everybody, not everbody.

****, ****, ****, ****...